<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2025 Workiva-->
<!--r:320018f8-5e38-4f73-a802-7c85c1aa5e94,g:366ded3c-a0b1-4b2a-b8ff-358570730c74-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member"/>
  <link:roleRef roleURI="http://www.cardinal.com/role/CondensedConsolidatedStatementsofShareholdersEquity" xlink:type="simple" xlink:href="cah-20241231.xsd#CondensedConsolidatedStatementsofShareholdersEquity"/>
  <link:definitionLink xlink:role="http://www.cardinal.com/role/CondensedConsolidatedStatementsofShareholdersEquity" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_14de3f1f-914b-4604-8bc8-4fcbce45a603" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_0a1f119c-1f9b-448e-87e1-344e14c6f501" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_14de3f1f-914b-4604-8bc8-4fcbce45a603" xlink:to="loc_us-gaap_StatementTable_0a1f119c-1f9b-448e-87e1-344e14c6f501" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_802901e6-ee58-404b-8cd6-2c7d3cf5771b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_0a1f119c-1f9b-448e-87e1-344e14c6f501" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_802901e6-ee58-404b-8cd6-2c7d3cf5771b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_802901e6-ee58-404b-8cd6-2c7d3cf5771b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_802901e6-ee58-404b-8cd6-2c7d3cf5771b" xlink:to="loc_us-gaap_EquityComponentDomain_802901e6-ee58-404b-8cd6-2c7d3cf5771b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_409941b0-1760-499a-ac1e-9ac302dc301c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_802901e6-ee58-404b-8cd6-2c7d3cf5771b" xlink:to="loc_us-gaap_EquityComponentDomain_409941b0-1760-499a-ac1e-9ac302dc301c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_9666e58a-33d0-4b19-b075-6e9d5f7e2582" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_409941b0-1760-499a-ac1e-9ac302dc301c" xlink:to="loc_us-gaap_CommonStockMember_9666e58a-33d0-4b19-b075-6e9d5f7e2582" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsMember_3fa6bfcf-e64b-46bd-93c1-70c4b2d7b97b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RetainedEarningsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_409941b0-1760-499a-ac1e-9ac302dc301c" xlink:to="loc_us-gaap_RetainedEarningsMember_3fa6bfcf-e64b-46bd-93c1-70c4b2d7b97b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockCommonMember_42a92096-7fe2-462c-acab-a62d6d9e24ea" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TreasuryStockCommonMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_409941b0-1760-499a-ac1e-9ac302dc301c" xlink:to="loc_us-gaap_TreasuryStockCommonMember_42a92096-7fe2-462c-acab-a62d6d9e24ea" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_9321b466-ab97-49f0-ac73-30b4474a3a75" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_409941b0-1760-499a-ac1e-9ac302dc301c" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_9321b466-ab97-49f0-ac73-30b4474a3a75" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoncontrollingInterestMember_5ce17408-d20c-4878-9a0b-cec9abe2b059" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NoncontrollingInterestMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_409941b0-1760-499a-ac1e-9ac302dc301c" xlink:to="loc_us-gaap_NoncontrollingInterestMember_5ce17408-d20c-4878-9a0b-cec9abe2b059" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockCommonMember_770210a9-0cee-4e2e-8372-70f46f46f07f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TreasuryStockCommonMember"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesIssued_5ca17049-0bcb-4be6-8240-d7c8b951b302" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommonStockSharesIssued"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_14de3f1f-914b-4604-8bc8-4fcbce45a603" xlink:to="loc_us-gaap_CommonStockSharesIssued_5ca17049-0bcb-4be6-8240-d7c8b951b302" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_bcd87461-61b9-44f3-8491-d56c0d822ac2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_14de3f1f-914b-4604-8bc8-4fcbce45a603" xlink:to="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_bcd87461-61b9-44f3-8491-d56c0d822ac2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockCommonShares_4eb83a0e-3e59-4891-abb2-81fb2b1eb677" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TreasuryStockCommonShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_14de3f1f-914b-4604-8bc8-4fcbce45a603" xlink:to="loc_us-gaap_TreasuryStockCommonShares_4eb83a0e-3e59-4891-abb2-81fb2b1eb677" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockValue_9fc1dfee-0683-4358-8777-f90cea8f7972" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TreasuryStockValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_14de3f1f-914b-4604-8bc8-4fcbce45a603" xlink:to="loc_us-gaap_TreasuryStockValue_9fc1dfee-0683-4358-8777-f90cea8f7972" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProfitLoss_652164be-44c8-45b6-a6aa-e902e8359149" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProfitLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_14de3f1f-914b-4604-8bc8-4fcbce45a603" xlink:to="loc_us-gaap_ProfitLoss_652164be-44c8-45b6-a6aa-e902e8359149" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_ecd8af2d-0abf-4a81-ad4c-8ab15c6de3e7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_14de3f1f-914b-4604-8bc8-4fcbce45a603" xlink:to="loc_us-gaap_NetIncomeLoss_ecd8af2d-0abf-4a81-ad4c-8ab15c6de3e7" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_3f625d30-3ce1-4634-b060-581ec7a55033" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_14de3f1f-914b-4604-8bc8-4fcbce45a603" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_3f625d30-3ce1-4634-b060-581ec7a55033" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_2e45d89c-4361-4efe-b847-8dcffe3214b0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_14de3f1f-914b-4604-8bc8-4fcbce45a603" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_2e45d89c-4361-4efe-b847-8dcffe3214b0" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoncontrollingInterestIncreaseFromBusinessCombination_4e78bd7e-239b-45a5-9ff4-bbad9aa33412" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NoncontrollingInterestIncreaseFromBusinessCombination"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_14de3f1f-914b-4604-8bc8-4fcbce45a603" xlink:to="loc_us-gaap_NoncontrollingInterestIncreaseFromBusinessCombination_4e78bd7e-239b-45a5-9ff4-bbad9aa33412" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_91800d4c-bca0-42e9-a5ea-ff9cfaa729e2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_14de3f1f-914b-4604-8bc8-4fcbce45a603" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_91800d4c-bca0-42e9-a5ea-ff9cfaa729e2" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_c38d506c-961c-45cc-96e9-21b0ee05e803" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_14de3f1f-914b-4604-8bc8-4fcbce45a603" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_c38d506c-961c-45cc-96e9-21b0ee05e803" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForRepurchaseOfCommonStock_d5256d60-2fe5-4ec4-8eda-7cd5e2497651" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsForRepurchaseOfCommonStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_14de3f1f-914b-4604-8bc8-4fcbce45a603" xlink:to="loc_us-gaap_PaymentsForRepurchaseOfCommonStock_d5256d60-2fe5-4ec4-8eda-7cd5e2497651" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockSharesAcquired_6186fd87-4a23-49d5-aac7-c972f59ae235" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TreasuryStockSharesAcquired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_14de3f1f-914b-4604-8bc8-4fcbce45a603" xlink:to="loc_us-gaap_TreasuryStockSharesAcquired_6186fd87-4a23-49d5-aac7-c972f59ae235" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockSharesRetired_0cab9c6e-959d-49e0-ae22-c2491d467d0d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TreasuryStockSharesRetired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_14de3f1f-914b-4604-8bc8-4fcbce45a603" xlink:to="loc_us-gaap_TreasuryStockSharesRetired_0cab9c6e-959d-49e0-ae22-c2491d467d0d" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Dividends_aabc7c34-61b2-4b5e-aa4a-3fcb16457154" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Dividends"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_14de3f1f-914b-4604-8bc8-4fcbce45a603" xlink:to="loc_us-gaap_Dividends_aabc7c34-61b2-4b5e-aa4a-3fcb16457154" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders_cde2996e-da7d-44f4-80cd-1228eca6b93b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_14de3f1f-914b-4604-8bc8-4fcbce45a603" xlink:to="loc_us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders_cde2996e-da7d-44f4-80cd-1228eca6b93b" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityOtherShares_85fe94c6-09f9-42ec-a287-2d3b45b86952" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockholdersEquityOtherShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_14de3f1f-914b-4604-8bc8-4fcbce45a603" xlink:to="loc_us-gaap_StockholdersEquityOtherShares_85fe94c6-09f9-42ec-a287-2d3b45b86952" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityOther_b171404d-d604-450d-a201-c9d76ea76524" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockholdersEquityOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_14de3f1f-914b-4604-8bc8-4fcbce45a603" xlink:to="loc_us-gaap_StockholdersEquityOther_b171404d-d604-450d-a201-c9d76ea76524" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesIssued_e1db6336-e5b4-43fc-9264-0461ebdfcacf" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommonStockSharesIssued"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_a26e2652-f69a-4b54-b3ca-58e1ca300082" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockCommonShares_77f3fa96-7856-4ba7-bb95-bc333a098543" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TreasuryStockCommonShares"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockValue_db17f362-7740-4271-9a51-17784ee43ebd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TreasuryStockValue"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_fee3c012-f980-4f41-8ced-c455e71539ac" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TreasuryStockValueAcquiredCostMethod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_14de3f1f-914b-4604-8bc8-4fcbce45a603" xlink:to="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_fee3c012-f980-4f41-8ced-c455e71539ac" xlink:type="arc" order="22"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockCommonShares_34746325-91cf-4f44-9ce7-d64faa288ad5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TreasuryStockCommonShares"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cardinal.com/role/BasisofPresentationandSummaryofSignificantAccountingPoliciesNarrativeRecentFinancialAccountingStandardsDetails" xlink:type="simple" xlink:href="cah-20241231.xsd#BasisofPresentationandSummaryofSignificantAccountingPoliciesNarrativeRecentFinancialAccountingStandardsDetails"/>
  <link:definitionLink xlink:role="http://www.cardinal.com/role/BasisofPresentationandSummaryofSignificantAccountingPoliciesNarrativeRecentFinancialAccountingStandardsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskLineItems_db9cb451-dee4-4b87-8943-9b516da0857e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ConcentrationRiskLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTable_9b5dc2bf-c4f2-4dfa-9421-cbf490c8edcb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ConcentrationRiskTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ConcentrationRiskLineItems_db9cb451-dee4-4b87-8943-9b516da0857e" xlink:to="loc_us-gaap_ConcentrationRiskTable_9b5dc2bf-c4f2-4dfa-9421-cbf490c8edcb" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MajorCustomersAxis_121193a2-2cc7-4670-96c4-e7d96b085caf" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MajorCustomersAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ConcentrationRiskTable_9b5dc2bf-c4f2-4dfa-9421-cbf490c8edcb" xlink:to="loc_srt_MajorCustomersAxis_121193a2-2cc7-4670-96c4-e7d96b085caf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_121193a2-2cc7-4670-96c4-e7d96b085caf_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MajorCustomersAxis_121193a2-2cc7-4670-96c4-e7d96b085caf" xlink:to="loc_srt_NameOfMajorCustomerDomain_121193a2-2cc7-4670-96c4-e7d96b085caf_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_a6eeca3d-d087-4f0c-8859-1f7dda830f34" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MajorCustomersAxis_121193a2-2cc7-4670-96c4-e7d96b085caf" xlink:to="loc_srt_NameOfMajorCustomerDomain_a6eeca3d-d087-4f0c-8859-1f7dda830f34" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_OptumRxMember_7378b5b1-f07e-430c-927b-c274a31edf26" xlink:href="cah-20241231.xsd#cah_OptumRxMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_a6eeca3d-d087-4f0c-8859-1f7dda830f34" xlink:to="loc_cah_OptumRxMember_7378b5b1-f07e-430c-927b-c274a31edf26" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_6475b07b-fc39-464e-8772-5f6260088d2f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ConcentrationRiskTable_9b5dc2bf-c4f2-4dfa-9421-cbf490c8edcb" xlink:to="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_6475b07b-fc39-464e-8772-5f6260088d2f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_6475b07b-fc39-464e-8772-5f6260088d2f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_6475b07b-fc39-464e-8772-5f6260088d2f" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_6475b07b-fc39-464e-8772-5f6260088d2f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_7d7225d4-e47a-4c56-903d-219831393948" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_6475b07b-fc39-464e-8772-5f6260088d2f" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_7d7225d4-e47a-4c56-903d-219831393948" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SalesRevenueNetMember_92487989-f820-4461-a778-a26459f10b37" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SalesRevenueNetMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskBenchmarkDomain_7d7225d4-e47a-4c56-903d-219831393948" xlink:to="loc_us-gaap_SalesRevenueNetMember_92487989-f820-4461-a778-a26459f10b37" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByTypeAxis_dc32a427-71c5-4ab3-b68f-d969f855857f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ConcentrationRiskByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ConcentrationRiskTable_9b5dc2bf-c4f2-4dfa-9421-cbf490c8edcb" xlink:to="loc_us-gaap_ConcentrationRiskByTypeAxis_dc32a427-71c5-4ab3-b68f-d969f855857f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_dc32a427-71c5-4ab3-b68f-d969f855857f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_dc32a427-71c5-4ab3-b68f-d969f855857f" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_dc32a427-71c5-4ab3-b68f-d969f855857f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_10d55014-869e-42b4-9abf-e8c3e3b6a001" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_dc32a427-71c5-4ab3-b68f-d969f855857f" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_10d55014-869e-42b4-9abf-e8c3e3b6a001" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CustomerConcentrationRiskMember_fdf52952-9c6f-4965-b972-5e000f4ee693" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CustomerConcentrationRiskMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskTypeDomain_10d55014-869e-42b4-9abf-e8c3e3b6a001" xlink:to="loc_us-gaap_CustomerConcentrationRiskMember_fdf52952-9c6f-4965-b972-5e000f4ee693" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_fa91f77b-1ac6-4739-aeb1-ec60f2246fef" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ConcentrationRiskTable_9b5dc2bf-c4f2-4dfa-9421-cbf490c8edcb" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_fa91f77b-1ac6-4739-aeb1-ec60f2246fef" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_fa91f77b-1ac6-4739-aeb1-ec60f2246fef_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_fa91f77b-1ac6-4739-aeb1-ec60f2246fef" xlink:to="loc_us-gaap_SegmentDomain_fa91f77b-1ac6-4739-aeb1-ec60f2246fef_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_e2f33da9-65a3-4cdc-a58b-4bedc55916fb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_fa91f77b-1ac6-4739-aeb1-ec60f2246fef" xlink:to="loc_us-gaap_SegmentDomain_e2f33da9-65a3-4cdc-a58b-4bedc55916fb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_PharmaceuticalAndSpecialtySolutionsMember_b6c62dfe-da7f-4154-8bc2-6bbba6b4ae36" xlink:href="cah-20241231.xsd#cah_PharmaceuticalAndSpecialtySolutionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_e2f33da9-65a3-4cdc-a58b-4bedc55916fb" xlink:to="loc_cah_PharmaceuticalAndSpecialtySolutionsMember_b6c62dfe-da7f-4154-8bc2-6bbba6b4ae36" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskPercentage1_d47192ff-ee28-4c3c-88d0-41a8baf99171" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ConcentrationRiskPercentage1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskLineItems_db9cb451-dee4-4b87-8943-9b516da0857e" xlink:to="loc_us-gaap_ConcentrationRiskPercentage1_d47192ff-ee28-4c3c-88d0-41a8baf99171" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cardinal.com/role/BusinessCombinationsandAssetAcquisitionsDetails" xlink:type="simple" xlink:href="cah-20241231.xsd#BusinessCombinationsandAssetAcquisitionsDetails"/>
  <link:definitionLink xlink:role="http://www.cardinal.com/role/BusinessCombinationsandAssetAcquisitionsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionLineItems_8285ea7a-12fd-4519-97fb-00e352449a01" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessAcquisitionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_0b21f586-4de1-4069-a4b4-3fdc7b5172af" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_8285ea7a-12fd-4519-97fb-00e352449a01" xlink:to="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_0b21f586-4de1-4069-a4b4-3fdc7b5172af" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_cd64a713-9669-46b0-9213-834151fa1a4e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_0b21f586-4de1-4069-a4b4-3fdc7b5172af" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_cd64a713-9669-46b0-9213-834151fa1a4e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_cd64a713-9669-46b0-9213-834151fa1a4e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_cd64a713-9669-46b0-9213-834151fa1a4e" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_cd64a713-9669-46b0-9213-834151fa1a4e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_e05d5dc1-ca74-49df-83dd-650d792c3c99" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_cd64a713-9669-46b0-9213-834151fa1a4e" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_e05d5dc1-ca74-49df-83dd-650d792c3c99" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CustomerContractsMember_a3b8d650-ea7a-4a2a-9985-6305098bdcf0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CustomerContractsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_e05d5dc1-ca74-49df-83dd-650d792c3c99" xlink:to="loc_us-gaap_CustomerContractsMember_a3b8d650-ea7a-4a2a-9985-6305098bdcf0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TrademarksAndTradeNamesMember_3799347b-68aa-4bd5-9c3a-b11fbb744eee" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TrademarksAndTradeNamesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_e05d5dc1-ca74-49df-83dd-650d792c3c99" xlink:to="loc_us-gaap_TrademarksAndTradeNamesMember_3799347b-68aa-4bd5-9c3a-b11fbb744eee" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_26bab0c3-55f7-4d8d-85db-1c028782be4c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_0b21f586-4de1-4069-a4b4-3fdc7b5172af" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_26bab0c3-55f7-4d8d-85db-1c028782be4c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_26bab0c3-55f7-4d8d-85db-1c028782be4c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_26bab0c3-55f7-4d8d-85db-1c028782be4c" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_26bab0c3-55f7-4d8d-85db-1c028782be4c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_45fb6d89-1eca-4f25-9fed-3e1caefbdcee" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_26bab0c3-55f7-4d8d-85db-1c028782be4c" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_45fb6d89-1eca-4f25-9fed-3e1caefbdcee" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_IONMember_9786bb4a-538f-428f-aa06-50b64da1e4ad" xlink:href="cah-20241231.xsd#cah_IONMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_45fb6d89-1eca-4f25-9fed-3e1caefbdcee" xlink:to="loc_cah_IONMember_9786bb4a-538f-428f-aa06-50b64da1e4ad" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_SpecialtyNetworksMember_70c3af75-dd49-4378-9c30-ad554384460e" xlink:href="cah-20241231.xsd#cah_SpecialtyNetworksMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_45fb6d89-1eca-4f25-9fed-3e1caefbdcee" xlink:to="loc_cah_SpecialtyNetworksMember_70c3af75-dd49-4378-9c30-ad554384460e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_ADSGMember_9b47db5f-f666-44ac-8613-47deb8e1e6f0" xlink:href="cah-20241231.xsd#cah_ADSGMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_45fb6d89-1eca-4f25-9fed-3e1caefbdcee" xlink:to="loc_cah_ADSGMember_9b47db5f-f666-44ac-8613-47deb8e1e6f0" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_GIAMember_8eb03872-60fa-40b6-87a3-49a9dd5d3310" xlink:href="cah-20241231.xsd#cah_GIAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_45fb6d89-1eca-4f25-9fed-3e1caefbdcee" xlink:to="loc_cah_GIAMember_8eb03872-60fa-40b6-87a3-49a9dd5d3310" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeAxis_5ab92875-6d5c-408a-a66c-ad892f3c15c5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MeasurementInputTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_0b21f586-4de1-4069-a4b4-3fdc7b5172af" xlink:to="loc_us-gaap_MeasurementInputTypeAxis_5ab92875-6d5c-408a-a66c-ad892f3c15c5" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeDomain_5ab92875-6d5c-408a-a66c-ad892f3c15c5_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MeasurementInputTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_MeasurementInputTypeAxis_5ab92875-6d5c-408a-a66c-ad892f3c15c5" xlink:to="loc_us-gaap_MeasurementInputTypeDomain_5ab92875-6d5c-408a-a66c-ad892f3c15c5_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeDomain_dfeb12f8-257e-46fc-bafb-9c157cbe5134" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MeasurementInputTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_MeasurementInputTypeAxis_5ab92875-6d5c-408a-a66c-ad892f3c15c5" xlink:to="loc_us-gaap_MeasurementInputTypeDomain_dfeb12f8-257e-46fc-bafb-9c157cbe5134" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputDiscountRateMember_0cd0bc73-ef6c-4042-883f-40ace6267b10" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MeasurementInputDiscountRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_dfeb12f8-257e-46fc-bafb-9c157cbe5134" xlink:to="loc_us-gaap_MeasurementInputDiscountRateMember_0cd0bc73-ef6c-4042-883f-40ace6267b10" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_a17dedac-07ca-4c82-9e52-e22cb121ecb6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsequentEventTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_0b21f586-4de1-4069-a4b4-3fdc7b5172af" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_a17dedac-07ca-4c82-9e52-e22cb121ecb6" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_a17dedac-07ca-4c82-9e52-e22cb121ecb6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_a17dedac-07ca-4c82-9e52-e22cb121ecb6" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_a17dedac-07ca-4c82-9e52-e22cb121ecb6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_003d49da-d547-463f-ba07-4d8ba39a9bc5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_a17dedac-07ca-4c82-9e52-e22cb121ecb6" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_003d49da-d547-463f-ba07-4d8ba39a9bc5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventMember_cb0142c4-181f-432d-ba1c-56ccbfb8343b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsequentEventMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_003d49da-d547-463f-ba07-4d8ba39a9bc5" xlink:to="loc_us-gaap_SubsequentEventMember_cb0142c4-181f-432d-ba1c-56ccbfb8343b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueAxis_3df0bd15-f35a-42de-9594-522fd900bc4b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ValuationTechniqueAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_0b21f586-4de1-4069-a4b4-3fdc7b5172af" xlink:to="loc_us-gaap_ValuationTechniqueAxis_3df0bd15-f35a-42de-9594-522fd900bc4b" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueDomain_3df0bd15-f35a-42de-9594-522fd900bc4b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ValuationTechniqueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ValuationTechniqueAxis_3df0bd15-f35a-42de-9594-522fd900bc4b" xlink:to="loc_us-gaap_ValuationTechniqueDomain_3df0bd15-f35a-42de-9594-522fd900bc4b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueDomain_7727a4c5-12b7-455d-9b3c-f19af962994e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ValuationTechniqueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ValuationTechniqueAxis_3df0bd15-f35a-42de-9594-522fd900bc4b" xlink:to="loc_us-gaap_ValuationTechniqueDomain_7727a4c5-12b7-455d-9b3c-f19af962994e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueDiscountedCashFlowMember_7fe2959d-9441-4d40-bcae-6d3412ceec7a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ValuationTechniqueDiscountedCashFlowMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_7727a4c5-12b7-455d-9b3c-f19af962994e" xlink:to="loc_us-gaap_ValuationTechniqueDiscountedCashFlowMember_7fe2959d-9441-4d40-bcae-6d3412ceec7a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireBusinessesGross_99e2eeef-a53c-4b3e-bdd4-8a47a49e1845" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsToAcquireBusinessesGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_8285ea7a-12fd-4519-97fb-00e352449a01" xlink:to="loc_us-gaap_PaymentsToAcquireBusinessesGross_99e2eeef-a53c-4b3e-bdd4-8a47a49e1845" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsNet_24376d88-8107-4d0c-af07-5382304e96d2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_8285ea7a-12fd-4519-97fb-00e352449a01" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsNet_24376d88-8107-4d0c-af07-5382304e96d2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles_08d1f6b1-7bcd-40e3-858b-12a95323a6d1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_8285ea7a-12fd-4519-97fb-00e352449a01" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles_08d1f6b1-7bcd-40e3-858b-12a95323a6d1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents_b268aa92-a4b0-45b1-9c28-7151b762f405" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_8285ea7a-12fd-4519-97fb-00e352449a01" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents_b268aa92-a4b0-45b1-9c28-7151b762f405" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesLongTermDebt_8fcef48d-c2ad-427d-ab60-127df34039db" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesLongTermDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_8285ea7a-12fd-4519-97fb-00e352449a01" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesLongTermDebt_8fcef48d-c2ad-427d-ab60-127df34039db" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables_2eb10df7-94fa-4728-9c6e-dc32eb7b2523" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_8285ea7a-12fd-4519-97fb-00e352449a01" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables_2eb10df7-94fa-4728-9c6e-dc32eb7b2523" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory_d4edcf2e-e8d4-4dc5-83bc-a0f91727b223" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_8285ea7a-12fd-4519-97fb-00e352449a01" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory_d4edcf2e-e8d4-4dc5-83bc-a0f91727b223" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets_becb8f2e-0b0d-447e-b525-2fa9f0940b4a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_8285ea7a-12fd-4519-97fb-00e352449a01" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets_becb8f2e-0b0d-447e-b525-2fa9f0940b4a" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment_1b9f06eb-0232-44c6-ab6f-6cc2416f55e1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_8285ea7a-12fd-4519-97fb-00e352449a01" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment_1b9f06eb-0232-44c6-ab6f-6cc2416f55e1" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets_1d5c960c-bb74-41de-963a-953214a144be" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_8285ea7a-12fd-4519-97fb-00e352449a01" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets_1d5c960c-bb74-41de-963a-953214a144be" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable_8da07dd9-7974-4679-a4aa-4dfc160e2fe2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_8285ea7a-12fd-4519-97fb-00e352449a01" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable_8da07dd9-7974-4679-a4aa-4dfc160e2fe2" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesOther_451773fe-3cc8-47fd-ac93-7f5c46e9fd70" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_8285ea7a-12fd-4519-97fb-00e352449a01" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesOther_451773fe-3cc8-47fd-ac93-7f5c46e9fd70" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesLongTermDebt_bffc6ef8-9ed0-4859-b7f4-b78f97b790b8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesLongTermDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_8285ea7a-12fd-4519-97fb-00e352449a01" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesLongTermDebt_bffc6ef8-9ed0-4859-b7f4-b78f97b790b8" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther_09fac1f8-ca52-4312-9066-882ec43d4eb5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_8285ea7a-12fd-4519-97fb-00e352449a01" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther_09fac1f8-ca52-4312-9066-882ec43d4eb5" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet_9dc3a8a8-ac36-4e23-9bc5-72a84a017b8e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_8285ea7a-12fd-4519-97fb-00e352449a01" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet_9dc3a8a8-ac36-4e23-9bc5-72a84a017b8e" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationAcquisitionOfLessThan100PercentNoncontrollingInterestFairValue_cb72429e-d5a1-4c38-9a01-de07199ec5f9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessCombinationAcquisitionOfLessThan100PercentNoncontrollingInterestFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_8285ea7a-12fd-4519-97fb-00e352449a01" xlink:to="loc_us-gaap_BusinessCombinationAcquisitionOfLessThan100PercentNoncontrollingInterestFairValue_cb72429e-d5a1-4c38-9a01-de07199ec5f9" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_825ac854-6620-430f-ace5-6af12e75e154" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Goodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_8285ea7a-12fd-4519-97fb-00e352449a01" xlink:to="loc_us-gaap_Goodwill_825ac854-6620-430f-ace5-6af12e75e154" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedLessNoncontrollingInterest_9146610b-5a0e-4d7e-93a5-2c3e98c3ef0f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedLessNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_8285ea7a-12fd-4519-97fb-00e352449a01" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedLessNoncontrollingInterest_9146610b-5a0e-4d7e-93a5-2c3e98c3ef0f" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsRemainingAmortizationPeriod1_02afe7be-e743-4496-8993-ac6fe4c37ef2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetsRemainingAmortizationPeriod1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_8285ea7a-12fd-4519-97fb-00e352449a01" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsRemainingAmortizationPeriod1_02afe7be-e743-4496-8993-ac6fe4c37ef2" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationAcquisitionRelatedCosts_53c5c532-415c-4265-aa9b-54a00843b547" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessCombinationAcquisitionRelatedCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_8285ea7a-12fd-4519-97fb-00e352449a01" xlink:to="loc_us-gaap_BusinessCombinationAcquisitionRelatedCosts_53c5c532-415c-4265-aa9b-54a00843b547" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationPriceOfAcquisitionExpected_fa385bd3-df5a-4a58-859a-567678487e08" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessCombinationPriceOfAcquisitionExpected"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_8285ea7a-12fd-4519-97fb-00e352449a01" xlink:to="loc_us-gaap_BusinessCombinationPriceOfAcquisitionExpected_fa385bd3-df5a-4a58-859a-567678487e08" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired_f6ec391d-bd55-4257-a629-28d4ed75cfdc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_8285ea7a-12fd-4519-97fb-00e352449a01" xlink:to="loc_us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired_f6ec391d-bd55-4257-a629-28d4ed75cfdc" xlink:type="arc" order="21"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_IntangibleAssetsMeasurementInput_0712dc08-5eef-433f-9425-8a34a8e23141" xlink:href="cah-20241231.xsd#cah_IntangibleAssetsMeasurementInput"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_8285ea7a-12fd-4519-97fb-00e352449a01" xlink:to="loc_cah_IntangibleAssetsMeasurementInput_0712dc08-5eef-433f-9425-8a34a8e23141" xlink:type="arc" order="22"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cardinal.com/role/DiscontinuedOperationsandDisposalGroupsDetails" xlink:type="simple" xlink:href="cah-20241231.xsd#DiscontinuedOperationsandDisposalGroupsDetails"/>
  <link:definitionLink xlink:role="http://www.cardinal.com/role/DiscontinuedOperationsandDisposalGroupsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_0a6ecbc3-3bab-463e-902f-f987f5a5cd82" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_513919c4-aab1-414e-9f6d-17ec700ad7e3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_0a6ecbc3-3bab-463e-902f-f987f5a5cd82" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_513919c4-aab1-414e-9f6d-17ec700ad7e3" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_749167a4-615b-4675-b147-7016195534f6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_513919c4-aab1-414e-9f6d-17ec700ad7e3" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_749167a4-615b-4675-b147-7016195534f6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_749167a4-615b-4675-b147-7016195534f6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_749167a4-615b-4675-b147-7016195534f6" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_749167a4-615b-4675-b147-7016195534f6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_923b316e-72f0-472b-8a6e-b0f7e151b587" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_749167a4-615b-4675-b147-7016195534f6" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_923b316e-72f0-472b-8a6e-b0f7e151b587" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_2a507cac-f322-4fa5-a298-48a09d998af7" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_513919c4-aab1-414e-9f6d-17ec700ad7e3" xlink:to="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_2a507cac-f322-4fa5-a298-48a09d998af7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_2a507cac-f322-4fa5-a298-48a09d998af7_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_2a507cac-f322-4fa5-a298-48a09d998af7" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_2a507cac-f322-4fa5-a298-48a09d998af7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_045e7904-83d6-491d-aace-32446fc42656" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_2a507cac-f322-4fa5-a298-48a09d998af7" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_045e7904-83d6-491d-aace-32446fc42656" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_TransactionDataSystemInvestmentMember_82a78507-1d66-4cb5-91df-21a57091b464" xlink:href="cah-20241231.xsd#cah_TransactionDataSystemInvestmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_045e7904-83d6-491d-aace-32446fc42656" xlink:to="loc_cah_TransactionDataSystemInvestmentMember_82a78507-1d66-4cb5-91df-21a57091b464" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_OutcomesDivestitureAxis_eb278a7b-700d-4c0c-b9b8-1ff893146e59" xlink:href="cah-20241231.xsd#cah_OutcomesDivestitureAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_513919c4-aab1-414e-9f6d-17ec700ad7e3" xlink:to="loc_cah_OutcomesDivestitureAxis_eb278a7b-700d-4c0c-b9b8-1ff893146e59" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_OutcomesDivestitureDomain_eb278a7b-700d-4c0c-b9b8-1ff893146e59_default" xlink:href="cah-20241231.xsd#cah_OutcomesDivestitureDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_cah_OutcomesDivestitureAxis_eb278a7b-700d-4c0c-b9b8-1ff893146e59" xlink:to="loc_cah_OutcomesDivestitureDomain_eb278a7b-700d-4c0c-b9b8-1ff893146e59_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_OutcomesDivestitureDomain_a402e46c-6483-4712-a272-63d99fe44460" xlink:href="cah-20241231.xsd#cah_OutcomesDivestitureDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_cah_OutcomesDivestitureAxis_eb278a7b-700d-4c0c-b9b8-1ff893146e59" xlink:to="loc_cah_OutcomesDivestitureDomain_a402e46c-6483-4712-a272-63d99fe44460" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_OutcomesDivestitureMember_51a5d52d-108a-454b-8659-ad906885e194" xlink:href="cah-20241231.xsd#cah_OutcomesDivestitureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_cah_OutcomesDivestitureDomain_a402e46c-6483-4712-a272-63d99fe44460" xlink:to="loc_cah_OutcomesDivestitureMember_51a5d52d-108a-454b-8659-ad906885e194" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestmentOwnershipPercentage_0546db53-47c4-44a1-a5e6-587a8cadb7c0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EquityMethodInvestmentOwnershipPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_0a6ecbc3-3bab-463e-902f-f987f5a5cd82" xlink:to="loc_us-gaap_EquityMethodInvestmentOwnershipPercentage_0546db53-47c4-44a1-a5e6-587a8cadb7c0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupNotDiscontinuedOperationGainLossOnDisposal_807777ab-4b54-40b6-b11c-c3beadb78118" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DisposalGroupNotDiscontinuedOperationGainLossOnDisposal"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_0a6ecbc3-3bab-463e-902f-f987f5a5cd82" xlink:to="loc_us-gaap_DisposalGroupNotDiscontinuedOperationGainLossOnDisposal_807777ab-4b54-40b6-b11c-c3beadb78118" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupNotDiscontinuedOperationGainLossOnDisposalStatementOfIncomeExtensibleList_07ae1bf5-75c0-42eb-a377-a6a54f30b8e0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DisposalGroupNotDiscontinuedOperationGainLossOnDisposalStatementOfIncomeExtensibleList"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_0a6ecbc3-3bab-463e-902f-f987f5a5cd82" xlink:to="loc_us-gaap_DisposalGroupNotDiscontinuedOperationGainLossOnDisposalStatementOfIncomeExtensibleList_07ae1bf5-75c0-42eb-a377-a6a54f30b8e0" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestmentsFairValueDisclosure_401b1c26-483d-49ad-8bfa-5cd0255f2883" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EquityMethodInvestmentsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_0a6ecbc3-3bab-463e-902f-f987f5a5cd82" xlink:to="loc_us-gaap_EquityMethodInvestmentsFairValueDisclosure_401b1c26-483d-49ad-8bfa-5cd0255f2883" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cardinal.com/role/RestructuringandEmployeeSeveranceLiabilitiesAssociatedwithRestructuringandEmployeeSeveranceActivitiesDetails" xlink:type="simple" xlink:href="cah-20241231.xsd#RestructuringandEmployeeSeveranceLiabilitiesAssociatedwithRestructuringandEmployeeSeveranceActivitiesDetails"/>
  <link:definitionLink xlink:role="http://www.cardinal.com/role/RestructuringandEmployeeSeveranceLiabilitiesAssociatedwithRestructuringandEmployeeSeveranceActivitiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringCostAndReserveLineItems_0985a2b5-766f-4548-89d9-31c6ec614229" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RestructuringCostAndReserveLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_dc3f7d19-d966-4baf-b6a2-89bda81660cb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfRestructuringAndRelatedCostsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_0985a2b5-766f-4548-89d9-31c6ec614229" xlink:to="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_dc3f7d19-d966-4baf-b6a2-89bda81660cb" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringCostAndReserveAxis_4ed8b070-de42-422e-9bf9-02515caf3ea5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RestructuringCostAndReserveAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_dc3f7d19-d966-4baf-b6a2-89bda81660cb" xlink:to="loc_us-gaap_RestructuringCostAndReserveAxis_4ed8b070-de42-422e-9bf9-02515caf3ea5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TypeOfRestructuringDomain_4ed8b070-de42-422e-9bf9-02515caf3ea5_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TypeOfRestructuringDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RestructuringCostAndReserveAxis_4ed8b070-de42-422e-9bf9-02515caf3ea5" xlink:to="loc_us-gaap_TypeOfRestructuringDomain_4ed8b070-de42-422e-9bf9-02515caf3ea5_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TypeOfRestructuringDomain_5df4f2d3-704a-4243-a352-80bc191ce1d5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TypeOfRestructuringDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RestructuringCostAndReserveAxis_4ed8b070-de42-422e-9bf9-02515caf3ea5" xlink:to="loc_us-gaap_TypeOfRestructuringDomain_5df4f2d3-704a-4243-a352-80bc191ce1d5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeSeveranceMember_65a1173d-da9a-4eaf-9e92-e07d0cb48f23" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EmployeeSeveranceMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfRestructuringDomain_5df4f2d3-704a-4243-a352-80bc191ce1d5" xlink:to="loc_us-gaap_EmployeeSeveranceMember_65a1173d-da9a-4eaf-9e92-e07d0cb48f23" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FacilityClosingMember_632bbb3e-c8e2-4fde-95fa-ec965ef69082" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FacilityClosingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfRestructuringDomain_5df4f2d3-704a-4243-a352-80bc191ce1d5" xlink:to="loc_us-gaap_FacilityClosingMember_632bbb3e-c8e2-4fde-95fa-ec965ef69082" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringReserveRollForward_b5e5b687-a604-444a-ad0a-67674a80eff3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RestructuringReserveRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_0985a2b5-766f-4548-89d9-31c6ec614229" xlink:to="loc_us-gaap_RestructuringReserveRollForward_b5e5b687-a604-444a-ad0a-67674a80eff3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringReserve_8281b3ff-0db2-43f4-b91b-3dcbb1c0647e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RestructuringReserve"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringReserveRollForward_b5e5b687-a604-444a-ad0a-67674a80eff3" xlink:to="loc_us-gaap_RestructuringReserve_8281b3ff-0db2-43f4-b91b-3dcbb1c0647e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringCosts_05287039-3080-4052-9771-8e694d66a070" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RestructuringCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringReserveRollForward_b5e5b687-a604-444a-ad0a-67674a80eff3" xlink:to="loc_us-gaap_RestructuringCosts_05287039-3080-4052-9771-8e694d66a070" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForRestructuring_37eefd88-8ff3-4352-b19e-443dfa8fd0c5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsForRestructuring"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringReserveRollForward_b5e5b687-a604-444a-ad0a-67674a80eff3" xlink:to="loc_us-gaap_PaymentsForRestructuring_37eefd88-8ff3-4352-b19e-443dfa8fd0c5" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringReserve_29db0b7f-58c7-4dd6-95bc-17c0e1098ea8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RestructuringReserve"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cardinal.com/role/RestructuringandEmployeeSeveranceNarativeDetails" xlink:type="simple" xlink:href="cah-20241231.xsd#RestructuringandEmployeeSeveranceNarativeDetails"/>
  <link:definitionLink xlink:role="http://www.cardinal.com/role/RestructuringandEmployeeSeveranceNarativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringCostAndReserveLineItems_a6426fe2-347f-4794-8c6c-5591bf96b9ce" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RestructuringCostAndReserveLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_b3764a67-2196-4da3-b4f8-24c96bdca7fe" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfRestructuringAndRelatedCostsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_a6426fe2-347f-4794-8c6c-5591bf96b9ce" xlink:to="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_b3764a67-2196-4da3-b4f8-24c96bdca7fe" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringPlanAxis_9e98d50b-c58e-402d-aa70-04d990af37c2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RestructuringPlanAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_b3764a67-2196-4da3-b4f8-24c96bdca7fe" xlink:to="loc_us-gaap_RestructuringPlanAxis_9e98d50b-c58e-402d-aa70-04d990af37c2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringPlanDomain_9e98d50b-c58e-402d-aa70-04d990af37c2_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RestructuringPlanDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RestructuringPlanAxis_9e98d50b-c58e-402d-aa70-04d990af37c2" xlink:to="loc_us-gaap_RestructuringPlanDomain_9e98d50b-c58e-402d-aa70-04d990af37c2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringPlanDomain_ac42fce2-5077-499a-a762-201281f0c9a8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RestructuringPlanDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RestructuringPlanAxis_9e98d50b-c58e-402d-aa70-04d990af37c2" xlink:to="loc_us-gaap_RestructuringPlanDomain_ac42fce2-5077-499a-a762-201281f0c9a8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeveranceCosts1_496df8ad-844e-4538-ae91-738e03660a0f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SeveranceCosts1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_a6426fe2-347f-4794-8c6c-5591bf96b9ce" xlink:to="loc_us-gaap_SeveranceCosts1_496df8ad-844e-4538-ae91-738e03660a0f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_FacilityExitAndOtherCosts_b9eac45c-d1b6-4b4e-862f-c2cf1fdf4519" xlink:href="cah-20241231.xsd#cah_FacilityExitAndOtherCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_a6426fe2-347f-4794-8c6c-5591bf96b9ce" xlink:to="loc_cah_FacilityExitAndOtherCosts_b9eac45c-d1b6-4b4e-862f-c2cf1fdf4519" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cardinal.com/role/GoodwillandOtherIntangibleAssetsScheduleofGoodwillbyReportableSegmentDetails" xlink:type="simple" xlink:href="cah-20241231.xsd#GoodwillandOtherIntangibleAssetsScheduleofGoodwillbyReportableSegmentDetails"/>
  <link:definitionLink xlink:role="http://www.cardinal.com/role/GoodwillandOtherIntangibleAssetsScheduleofGoodwillbyReportableSegmentDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillLineItems_0d7353b0-e7af-41b8-82b1-6cbda9bf6417" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GoodwillLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfGoodwillTable_cfea781e-89b5-4a70-a050-74f973b07a61" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfGoodwillTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_GoodwillLineItems_0d7353b0-e7af-41b8-82b1-6cbda9bf6417" xlink:to="loc_us-gaap_ScheduleOfGoodwillTable_cfea781e-89b5-4a70-a050-74f973b07a61" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_b1af2170-ec79-4ec8-9792-ed74d33f3dcb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfGoodwillTable_cfea781e-89b5-4a70-a050-74f973b07a61" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_b1af2170-ec79-4ec8-9792-ed74d33f3dcb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_b1af2170-ec79-4ec8-9792-ed74d33f3dcb_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_b1af2170-ec79-4ec8-9792-ed74d33f3dcb" xlink:to="loc_us-gaap_SegmentDomain_b1af2170-ec79-4ec8-9792-ed74d33f3dcb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_a1f3359b-3e2f-4806-a5af-c450ef88e66e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_b1af2170-ec79-4ec8-9792-ed74d33f3dcb" xlink:to="loc_us-gaap_SegmentDomain_a1f3359b-3e2f-4806-a5af-c450ef88e66e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_PharmaceuticalAndSpecialtySolutionsMember_e7d07a15-662e-4c46-9f2e-1651bf70b22f" xlink:href="cah-20241231.xsd#cah_PharmaceuticalAndSpecialtySolutionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_a1f3359b-3e2f-4806-a5af-c450ef88e66e" xlink:to="loc_cah_PharmaceuticalAndSpecialtySolutionsMember_e7d07a15-662e-4c46-9f2e-1651bf70b22f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_GMPDMember_c10065d4-ba24-49a8-b99c-46e29dab0663" xlink:href="cah-20241231.xsd#cah_GMPDMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_a1f3359b-3e2f-4806-a5af-c450ef88e66e" xlink:to="loc_cah_GMPDMember_c10065d4-ba24-49a8-b99c-46e29dab0663" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllOtherSegmentsMember_0d2e6acb-f1ad-4943-a62d-891516eba1e2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AllOtherSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_a1f3359b-3e2f-4806-a5af-c450ef88e66e" xlink:to="loc_us-gaap_AllOtherSegmentsMember_0d2e6acb-f1ad-4943-a62d-891516eba1e2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillRollForward_a0e3257b-6311-4a8f-9770-db160ff15ec9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GoodwillRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillLineItems_0d7353b0-e7af-41b8-82b1-6cbda9bf6417" xlink:to="loc_us-gaap_GoodwillRollForward_a0e3257b-6311-4a8f-9770-db160ff15ec9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_337dffa1-d7c0-409b-bdc6-83790dcffd3e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Goodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillRollForward_a0e3257b-6311-4a8f-9770-db160ff15ec9" xlink:to="loc_us-gaap_Goodwill_337dffa1-d7c0-409b-bdc6-83790dcffd3e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillAcquiredDuringPeriod_f005be7b-21e2-4df0-b536-d961bc6c1799" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GoodwillAcquiredDuringPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillRollForward_a0e3257b-6311-4a8f-9770-db160ff15ec9" xlink:to="loc_us-gaap_GoodwillAcquiredDuringPeriod_f005be7b-21e2-4df0-b536-d961bc6c1799" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_c3798c12-0729-4955-9949-58bf026c3b0a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Goodwill"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillImpairmentLoss_f44620f4-66b7-4fa2-8425-0744825aba59" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GoodwillImpairmentLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillRollForward_a0e3257b-6311-4a8f-9770-db160ff15ec9" xlink:to="loc_us-gaap_GoodwillImpairmentLoss_f44620f4-66b7-4fa2-8425-0744825aba59" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cardinal.com/role/GoodwillandOtherIntangibleAssetsScheduleofIntangibleAssetsDetails" xlink:type="simple" xlink:href="cah-20241231.xsd#GoodwillandOtherIntangibleAssetsScheduleofIntangibleAssetsDetails"/>
  <link:definitionLink xlink:role="http://www.cardinal.com/role/GoodwillandOtherIntangibleAssetsScheduleofIntangibleAssetsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassLineItems_ad815359-d36b-4779-a086-5344eec7389c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfIndefiniteLivedIntangibleAssetsTable_6d947704-7959-4bd0-a50c-387eb3ec2a90" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfIndefiniteLivedIntangibleAssetsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassLineItems_ad815359-d36b-4779-a086-5344eec7389c" xlink:to="loc_us-gaap_ScheduleOfIndefiniteLivedIntangibleAssetsTable_6d947704-7959-4bd0-a50c-387eb3ec2a90" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis_a6a34c33-3f3d-45fc-83e5-4d862a60f4f9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfIndefiniteLivedIntangibleAssetsTable_6d947704-7959-4bd0-a50c-387eb3ec2a90" xlink:to="loc_us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis_a6a34c33-3f3d-45fc-83e5-4d862a60f4f9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain_a6a34c33-3f3d-45fc-83e5-4d862a60f4f9_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis_a6a34c33-3f3d-45fc-83e5-4d862a60f4f9" xlink:to="loc_us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain_a6a34c33-3f3d-45fc-83e5-4d862a60f4f9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain_0fdb8f2e-3705-4727-bfa5-ff91572b0bf5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis_a6a34c33-3f3d-45fc-83e5-4d862a60f4f9" xlink:to="loc_us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain_0fdb8f2e-3705-4727-bfa5-ff91572b0bf5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_IPRDTrademarksandOtherMember_2ae0988a-17dd-4ded-9733-69dc976d0431" xlink:href="cah-20241231.xsd#cah_IPRDTrademarksandOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain_0fdb8f2e-3705-4727-bfa5-ff91572b0bf5" xlink:to="loc_cah_IPRDTrademarksandOtherMember_2ae0988a-17dd-4ded-9733-69dc976d0431" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_6815385f-4327-4fe8-9412-04d0ac6ff48b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassLineItems_ad815359-d36b-4779-a086-5344eec7389c" xlink:to="loc_us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_6815385f-4327-4fe8-9412-04d0ac6ff48b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_10386877-bdd5-4920-b1c7-ace24d89b543" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_d224b1b5-3cf4-44de-9541-505cbe5c9ee3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_10386877-bdd5-4920-b1c7-ace24d89b543" xlink:to="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_d224b1b5-3cf4-44de-9541-505cbe5c9ee3" xlink:type="arc" order="2" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_77f68d1d-ed1a-4767-8038-c8490c501f5b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_d224b1b5-3cf4-44de-9541-505cbe5c9ee3" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_77f68d1d-ed1a-4767-8038-c8490c501f5b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_77f68d1d-ed1a-4767-8038-c8490c501f5b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_77f68d1d-ed1a-4767-8038-c8490c501f5b" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_77f68d1d-ed1a-4767-8038-c8490c501f5b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_e5021022-e400-437d-a1fe-783e8f3b811a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_77f68d1d-ed1a-4767-8038-c8490c501f5b" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_e5021022-e400-437d-a1fe-783e8f3b811a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CustomerRelationshipsMember_15360414-f149-4d09-aedd-ee2091c0f3e5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CustomerRelationshipsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_e5021022-e400-437d-a1fe-783e8f3b811a" xlink:to="loc_us-gaap_CustomerRelationshipsMember_15360414-f149-4d09-aedd-ee2091c0f3e5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_TrademarksAndPatentsMember_afbdd0ae-2b37-4ccb-8947-4b0f1fa9cc51" xlink:href="cah-20241231.xsd#cah_TrademarksAndPatentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_e5021022-e400-437d-a1fe-783e8f3b811a" xlink:to="loc_cah_TrademarksAndPatentsMember_afbdd0ae-2b37-4ccb-8947-4b0f1fa9cc51" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DevelopedTechnologyRightsMember_1f116172-af4f-43f8-887a-47c8e26b6520" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DevelopedTechnologyRightsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_e5021022-e400-437d-a1fe-783e8f3b811a" xlink:to="loc_us-gaap_DevelopedTechnologyRightsMember_1f116172-af4f-43f8-887a-47c8e26b6520" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CustomerContractsMember_81cbc6df-eec7-479e-951a-77cc53b4bb53" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CustomerContractsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_e5021022-e400-437d-a1fe-783e8f3b811a" xlink:to="loc_us-gaap_CustomerContractsMember_81cbc6df-eec7-479e-951a-77cc53b4bb53" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsGross_0958db17-f6fc-4e58-8e0c-d73bb9e2b90d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetsGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_10386877-bdd5-4920-b1c7-ace24d89b543" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsGross_0958db17-f6fc-4e58-8e0c-d73bb9e2b90d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_28f46979-ecdf-4319-aaa5-7966b6a393dd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_10386877-bdd5-4920-b1c7-ace24d89b543" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_28f46979-ecdf-4319-aaa5-7966b6a393dd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsNet_54c8d42d-9bed-4a17-b668-b690012de3f4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_10386877-bdd5-4920-b1c7-ace24d89b543" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsNet_54c8d42d-9bed-4a17-b668-b690012de3f4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsRemainingAmortizationPeriod1_fd5bb456-6318-4c9e-8c15-65978cb55518" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FiniteLivedIntangibleAssetsRemainingAmortizationPeriod1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_10386877-bdd5-4920-b1c7-ace24d89b543" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsRemainingAmortizationPeriod1_fd5bb456-6318-4c9e-8c15-65978cb55518" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cardinal.com/role/GoodwillandOtherIntangibleAssetsNarrativeDetails" xlink:type="simple" xlink:href="cah-20241231.xsd#GoodwillandOtherIntangibleAssetsNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.cardinal.com/role/GoodwillandOtherIntangibleAssetsNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillLineItems_10311fcd-d63a-460f-a0e2-c50b657a6cd2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GoodwillLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfGoodwillTable_29ec95e0-3af3-41c8-9d4f-d0280e216af4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfGoodwillTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_GoodwillLineItems_10311fcd-d63a-460f-a0e2-c50b657a6cd2" xlink:to="loc_us-gaap_ScheduleOfGoodwillTable_29ec95e0-3af3-41c8-9d4f-d0280e216af4" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReportingUnitAxis_c137b7a5-c2e3-47f7-a524-e337b4ea7319" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ReportingUnitAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfGoodwillTable_29ec95e0-3af3-41c8-9d4f-d0280e216af4" xlink:to="loc_us-gaap_ReportingUnitAxis_c137b7a5-c2e3-47f7-a524-e337b4ea7319" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReportingUnitDomain_c137b7a5-c2e3-47f7-a524-e337b4ea7319_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ReportingUnitDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ReportingUnitAxis_c137b7a5-c2e3-47f7-a524-e337b4ea7319" xlink:to="loc_us-gaap_ReportingUnitDomain_c137b7a5-c2e3-47f7-a524-e337b4ea7319_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReportingUnitDomain_28d78c92-27d3-465f-99bf-bcf0debcc139" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ReportingUnitDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ReportingUnitAxis_c137b7a5-c2e3-47f7-a524-e337b4ea7319" xlink:to="loc_us-gaap_ReportingUnitDomain_28d78c92-27d3-465f-99bf-bcf0debcc139" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_GMPDMember_b1cab836-8f9b-4cae-9062-b030dd01c252" xlink:href="cah-20241231.xsd#cah_GMPDMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReportingUnitDomain_28d78c92-27d3-465f-99bf-bcf0debcc139" xlink:to="loc_cah_GMPDMember_b1cab836-8f9b-4cae-9062-b030dd01c252" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_aae14c17-943f-4f1d-8d6d-731e59de05fc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfGoodwillTable_29ec95e0-3af3-41c8-9d4f-d0280e216af4" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_aae14c17-943f-4f1d-8d6d-731e59de05fc" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_aae14c17-943f-4f1d-8d6d-731e59de05fc_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_aae14c17-943f-4f1d-8d6d-731e59de05fc" xlink:to="loc_us-gaap_SegmentDomain_aae14c17-943f-4f1d-8d6d-731e59de05fc_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_3ca3c7ae-2fc4-40c8-b015-a6c9178106f7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_aae14c17-943f-4f1d-8d6d-731e59de05fc" xlink:to="loc_us-gaap_SegmentDomain_3ca3c7ae-2fc4-40c8-b015-a6c9178106f7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_GMPDMember_55b77581-b129-45d8-9a88-087aa55e522c" xlink:href="cah-20241231.xsd#cah_GMPDMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_3ca3c7ae-2fc4-40c8-b015-a6c9178106f7" xlink:to="loc_cah_GMPDMember_55b77581-b129-45d8-9a88-087aa55e522c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_b8bf1004-771b-4bfe-8f0c-cc97047d9332" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Goodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillLineItems_10311fcd-d63a-460f-a0e2-c50b657a6cd2" xlink:to="loc_us-gaap_Goodwill_b8bf1004-771b-4bfe-8f0c-cc97047d9332" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillImpairmentLoss_c04a1af8-c29b-4d57-914a-75da588ad181" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GoodwillImpairmentLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillLineItems_10311fcd-d63a-460f-a0e2-c50b657a6cd2" xlink:to="loc_us-gaap_GoodwillImpairmentLoss_c04a1af8-c29b-4d57-914a-75da588ad181" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cardinal.com/role/LongTermObligationsandOtherShortTermBorrowingsDetails" xlink:type="simple" xlink:href="cah-20241231.xsd#LongTermObligationsandOtherShortTermBorrowingsDetails"/>
  <link:definitionLink xlink:role="http://www.cardinal.com/role/LongTermObligationsandOtherShortTermBorrowingsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_f2aa210c-4cdf-4f67-969a-fb6744850c27" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_d94c46ab-92ff-4e21-9e2a-696c0f70629e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_f2aa210c-4cdf-4f67-969a-fb6744850c27" xlink:to="loc_us-gaap_DebtInstrumentTable_d94c46ab-92ff-4e21-9e2a-696c0f70629e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_b238ab19-8752-478d-b007-652c2dbaa86a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_d94c46ab-92ff-4e21-9e2a-696c0f70629e" xlink:to="loc_us-gaap_DebtInstrumentAxis_b238ab19-8752-478d-b007-652c2dbaa86a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_b238ab19-8752-478d-b007-652c2dbaa86a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_b238ab19-8752-478d-b007-652c2dbaa86a" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_b238ab19-8752-478d-b007-652c2dbaa86a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_4098abbf-8fd0-41aa-8679-cf6fea1efc56" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_b238ab19-8752-478d-b007-652c2dbaa86a" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_4098abbf-8fd0-41aa-8679-cf6fea1efc56" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_A3.5NotesDue2024Member_024acd6e-b639-4723-983c-0d769ef2f344" xlink:href="cah-20241231.xsd#cah_A3.5NotesDue2024Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_4098abbf-8fd0-41aa-8679-cf6fea1efc56" xlink:to="loc_cah_A3.5NotesDue2024Member_024acd6e-b639-4723-983c-0d769ef2f344" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_A3.75NotesDue2025Member_d2ad331c-9afd-4e77-bef8-d84651571796" xlink:href="cah-20241231.xsd#cah_A3.75NotesDue2025Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_4098abbf-8fd0-41aa-8679-cf6fea1efc56" xlink:to="loc_cah_A3.75NotesDue2025Member_d2ad331c-9afd-4e77-bef8-d84651571796" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_A3.41Notesdue2027Member_ef3de0e5-4687-4ab5-b02f-1b0ee52d582e" xlink:href="cah-20241231.xsd#cah_A3.41Notesdue2027Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_4098abbf-8fd0-41aa-8679-cf6fea1efc56" xlink:to="loc_cah_A3.41Notesdue2027Member_ef3de0e5-4687-4ab5-b02f-1b0ee52d582e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_A5.125NotesDue2029Member_dbb77b2a-4997-4709-ab80-cbe4ad54cd4b" xlink:href="cah-20241231.xsd#cah_A5.125NotesDue2029Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_4098abbf-8fd0-41aa-8679-cf6fea1efc56" xlink:to="loc_cah_A5.125NotesDue2029Member_dbb77b2a-4997-4709-ab80-cbe4ad54cd4b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_A5.45NotesDue2034Member_4a03f88e-89b9-4e8e-9af0-a8298c84613b" xlink:href="cah-20241231.xsd#cah_A5.45NotesDue2034Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_4098abbf-8fd0-41aa-8679-cf6fea1efc56" xlink:to="loc_cah_A5.45NotesDue2034Member_4a03f88e-89b9-4e8e-9af0-a8298c84613b" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_A4.6Notesdue2043Member_871561ed-980f-42c1-9002-dc8701325f4a" xlink:href="cah-20241231.xsd#cah_A4.6Notesdue2043Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_4098abbf-8fd0-41aa-8679-cf6fea1efc56" xlink:to="loc_cah_A4.6Notesdue2043Member_871561ed-980f-42c1-9002-dc8701325f4a" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_A4.5Notesdue2044Member_904e5d39-2ea2-4882-ba68-37ba62bdea74" xlink:href="cah-20241231.xsd#cah_A4.5Notesdue2044Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_4098abbf-8fd0-41aa-8679-cf6fea1efc56" xlink:to="loc_cah_A4.5Notesdue2044Member_904e5d39-2ea2-4882-ba68-37ba62bdea74" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_A4.9Notesdue2045Member_21718bb2-46e1-4079-97d5-61a793ddde6e" xlink:href="cah-20241231.xsd#cah_A4.9Notesdue2045Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_4098abbf-8fd0-41aa-8679-cf6fea1efc56" xlink:to="loc_cah_A4.9Notesdue2045Member_21718bb2-46e1-4079-97d5-61a793ddde6e" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_A4.368Notesdue2047Member_1283b8ae-9cc5-4fab-82a9-16d21aa7f9c2" xlink:href="cah-20241231.xsd#cah_A4.368Notesdue2047Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_4098abbf-8fd0-41aa-8679-cf6fea1efc56" xlink:to="loc_cah_A4.368Notesdue2047Member_1283b8ae-9cc5-4fab-82a9-16d21aa7f9c2" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_A7.0Debenturesduefiscal2027Member_258bb9b2-2c6e-4c7e-b77b-35a6d72c3cd7" xlink:href="cah-20241231.xsd#cah_A7.0Debenturesduefiscal2027Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_4098abbf-8fd0-41aa-8679-cf6fea1efc56" xlink:to="loc_cah_A7.0Debenturesduefiscal2027Member_258bb9b2-2c6e-4c7e-b77b-35a6d72c3cd7" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_A5.0NotesDue2029Member_0a1de91d-d3ca-42f2-a4b2-af1d8e4b6c40" xlink:href="cah-20241231.xsd#cah_A5.0NotesDue2029Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_4098abbf-8fd0-41aa-8679-cf6fea1efc56" xlink:to="loc_cah_A5.0NotesDue2029Member_0a1de91d-d3ca-42f2-a4b2-af1d8e4b6c40" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_A5.35NotesDue2034Member_4c3935ff-354f-4c79-b529-7a54ee1074c3" xlink:href="cah-20241231.xsd#cah_A5.35NotesDue2034Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_4098abbf-8fd0-41aa-8679-cf6fea1efc56" xlink:to="loc_cah_A5.35NotesDue2034Member_4c3935ff-354f-4c79-b529-7a54ee1074c3" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_A5.75NotesDue2054Member_b391b3e7-fd69-4c62-8ad8-a2be9371dad8" xlink:href="cah-20241231.xsd#cah_A5.75NotesDue2054Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_4098abbf-8fd0-41aa-8679-cf6fea1efc56" xlink:to="loc_cah_A5.75NotesDue2054Member_b391b3e7-fd69-4c62-8ad8-a2be9371dad8" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_A4.7NotesDue2026Member_31088b67-589f-44da-9122-0b9a61f0f403" xlink:href="cah-20241231.xsd#cah_A4.7NotesDue2026Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_4098abbf-8fd0-41aa-8679-cf6fea1efc56" xlink:to="loc_cah_A4.7NotesDue2026Member_31088b67-589f-44da-9122-0b9a61f0f403" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_98feec1e-9542-4fd2-8820-d41a0174fbf8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_d94c46ab-92ff-4e21-9e2a-696c0f70629e" xlink:to="loc_us-gaap_CreditFacilityAxis_98feec1e-9542-4fd2-8820-d41a0174fbf8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_98feec1e-9542-4fd2-8820-d41a0174fbf8_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_98feec1e-9542-4fd2-8820-d41a0174fbf8" xlink:to="loc_us-gaap_CreditFacilityDomain_98feec1e-9542-4fd2-8820-d41a0174fbf8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_f9498543-9bc1-409e-96de-8ad00120eb95" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_98feec1e-9542-4fd2-8820-d41a0174fbf8" xlink:to="loc_us-gaap_CreditFacilityDomain_f9498543-9bc1-409e-96de-8ad00120eb95" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialPaperMember_e95885f9-71f7-4462-a051-072a928de3c8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommercialPaperMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_f9498543-9bc1-409e-96de-8ad00120eb95" xlink:to="loc_us-gaap_CommercialPaperMember_e95885f9-71f7-4462-a051-072a928de3c8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_7835fe4a-9224-4588-bbf6-67d674cac7de" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RevolvingCreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_f9498543-9bc1-409e-96de-8ad00120eb95" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_7835fe4a-9224-4588-bbf6-67d674cac7de" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_ShortTermCreditFacilitiesMember_df2a4e6e-b3d8-4062-a7a8-a18d0c23ee3e" xlink:href="cah-20241231.xsd#cah_ShortTermCreditFacilitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_f9498543-9bc1-409e-96de-8ad00120eb95" xlink:to="loc_cah_ShortTermCreditFacilitiesMember_df2a4e6e-b3d8-4062-a7a8-a18d0c23ee3e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_CommittedReceivablesSalesFacilityProgramMember_cd592a17-7d8f-4acc-9eeb-7d3ac55ceb41" xlink:href="cah-20241231.xsd#cah_CommittedReceivablesSalesFacilityProgramMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_f9498543-9bc1-409e-96de-8ad00120eb95" xlink:to="loc_cah_CommittedReceivablesSalesFacilityProgramMember_cd592a17-7d8f-4acc-9eeb-7d3ac55ceb41" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_CreditAgreementMember_fde6e8a1-e208-4633-a5ae-9dd8f7fad652" xlink:href="cah-20241231.xsd#cah_CreditAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_f9498543-9bc1-409e-96de-8ad00120eb95" xlink:to="loc_cah_CreditAgreementMember_fde6e8a1-e208-4633-a5ae-9dd8f7fad652" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_A364DadRevolvingCreditFacilityMember_e80f85cc-0dd0-4429-8487-a74454efd4fc" xlink:href="cah-20241231.xsd#cah_A364DadRevolvingCreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_f9498543-9bc1-409e-96de-8ad00120eb95" xlink:to="loc_cah_A364DadRevolvingCreditFacilityMember_e80f85cc-0dd0-4429-8487-a74454efd4fc" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BridgeLoanMember_28ec3081-79d4-4cd1-9594-bfd2f3c16c45" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BridgeLoanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_f9498543-9bc1-409e-96de-8ad00120eb95" xlink:to="loc_us-gaap_BridgeLoanMember_28ec3081-79d4-4cd1-9594-bfd2f3c16c45" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShortTermDebtTypeAxis_f562bb35-8125-4959-ba37-80bc9a18d664" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShortTermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_d94c46ab-92ff-4e21-9e2a-696c0f70629e" xlink:to="loc_us-gaap_ShortTermDebtTypeAxis_f562bb35-8125-4959-ba37-80bc9a18d664" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShortTermDebtTypeDomain_f562bb35-8125-4959-ba37-80bc9a18d664_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShortTermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ShortTermDebtTypeAxis_f562bb35-8125-4959-ba37-80bc9a18d664" xlink:to="loc_us-gaap_ShortTermDebtTypeDomain_f562bb35-8125-4959-ba37-80bc9a18d664_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShortTermDebtTypeDomain_7885fabb-a84a-4f2e-9fd1-eb1dda5454c8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShortTermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ShortTermDebtTypeAxis_f562bb35-8125-4959-ba37-80bc9a18d664" xlink:to="loc_us-gaap_ShortTermDebtTypeDomain_7885fabb-a84a-4f2e-9fd1-eb1dda5454c8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_BackstopCreditFacilityMember_8ba30883-1115-484e-8eb8-60794d71084a" xlink:href="cah-20241231.xsd#cah_BackstopCreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShortTermDebtTypeDomain_7885fabb-a84a-4f2e-9fd1-eb1dda5454c8" xlink:to="loc_cah_BackstopCreditFacilityMember_8ba30883-1115-484e-8eb8-60794d71084a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementScenarioAxis_b21194a5-6172-4486-b269-b96c568c0c28" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_StatementScenarioAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_d94c46ab-92ff-4e21-9e2a-696c0f70629e" xlink:to="loc_srt_StatementScenarioAxis_b21194a5-6172-4486-b269-b96c568c0c28" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioUnspecifiedDomain_b21194a5-6172-4486-b269-b96c568c0c28_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ScenarioUnspecifiedDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementScenarioAxis_b21194a5-6172-4486-b269-b96c568c0c28" xlink:to="loc_srt_ScenarioUnspecifiedDomain_b21194a5-6172-4486-b269-b96c568c0c28_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioUnspecifiedDomain_806fc779-2a09-4a9e-b765-cc3e13f87ff4" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ScenarioUnspecifiedDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementScenarioAxis_b21194a5-6172-4486-b269-b96c568c0c28" xlink:to="loc_srt_ScenarioUnspecifiedDomain_806fc779-2a09-4a9e-b765-cc3e13f87ff4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioForecastMember_05d99f9b-df5d-4f25-b046-61e88bd00a20" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ScenarioForecastMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ScenarioUnspecifiedDomain_806fc779-2a09-4a9e-b765-cc3e13f87ff4" xlink:to="loc_srt_ScenarioForecastMember_05d99f9b-df5d-4f25-b046-61e88bd00a20" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NotesPayable_a9d99158-79b5-4447-ac86-98babb061ef7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NotesPayable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_f2aa210c-4cdf-4f67-969a-fb6744850c27" xlink:to="loc_us-gaap_NotesPayable_a9d99158-79b5-4447-ac86-98babb061ef7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherBorrowings_3be93bbb-f3dd-43bf-bfca-b00038731351" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherBorrowings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_f2aa210c-4cdf-4f67-969a-fb6744850c27" xlink:to="loc_us-gaap_OtherBorrowings_3be93bbb-f3dd-43bf-bfca-b00038731351" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtAndCapitalLeaseObligations_95aa8706-51c4-41f3-8989-b180ceb9ad22" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtAndCapitalLeaseObligations"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_f2aa210c-4cdf-4f67-969a-fb6744850c27" xlink:to="loc_us-gaap_DebtAndCapitalLeaseObligations_95aa8706-51c4-41f3-8989-b180ceb9ad22" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsCurrent_9fdafc0f-ef98-453c-a461-a0e160966e74" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongTermDebtAndCapitalLeaseObligationsCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_f2aa210c-4cdf-4f67-969a-fb6744850c27" xlink:to="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsCurrent_9fdafc0f-ef98-453c-a461-a0e160966e74" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtAndCapitalLeaseObligations_bfc3fa6f-e487-4cae-9bc6-8a542fbc1639" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongTermDebtAndCapitalLeaseObligations"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_f2aa210c-4cdf-4f67-969a-fb6744850c27" xlink:to="loc_us-gaap_LongTermDebtAndCapitalLeaseObligations_bfc3fa6f-e487-4cae-9bc6-8a542fbc1639" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths_aa5dcded-4a23-4ef6-8177-c193e88871dd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_f2aa210c-4cdf-4f67-969a-fb6744850c27" xlink:to="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths_aa5dcded-4a23-4ef6-8177-c193e88871dd" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo_3d5ea814-5cca-4621-ae20-798bb1a60660" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_f2aa210c-4cdf-4f67-969a-fb6744850c27" xlink:to="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo_3d5ea814-5cca-4621-ae20-798bb1a60660" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree_1b02882d-ac66-4646-a30d-fc135d88c314" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_f2aa210c-4cdf-4f67-969a-fb6744850c27" xlink:to="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree_1b02882d-ac66-4646-a30d-fc135d88c314" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour_26db01a0-3f61-4a40-b226-fc6dca99339c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_f2aa210c-4cdf-4f67-969a-fb6744850c27" xlink:to="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour_26db01a0-3f61-4a40-b226-fc6dca99339c" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive_dc9ee6ff-da47-4103-8bcb-068bc27a949c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_f2aa210c-4cdf-4f67-969a-fb6744850c27" xlink:to="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive_dc9ee6ff-da47-4103-8bcb-068bc27a949c" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive_0cc67ae8-f645-437c-9da5-4c1978815c1c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_f2aa210c-4cdf-4f67-969a-fb6744850c27" xlink:to="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive_0cc67ae8-f645-437c-9da5-4c1978815c1c" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_TotalLongTermandShortTermObligations_2ae21eae-d079-4b6e-be53-f8ddc2a7588a" xlink:href="cah-20241231.xsd#cah_TotalLongTermandShortTermObligations"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_f2aa210c-4cdf-4f67-969a-fb6744850c27" xlink:to="loc_cah_TotalLongTermandShortTermObligations_2ae21eae-d079-4b6e-be53-f8ddc2a7588a" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsPayableCurrentAndNoncurrent_4d32d01d-0394-4080-86e7-711c69e447cb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccountsPayableCurrentAndNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_f2aa210c-4cdf-4f67-969a-fb6744850c27" xlink:to="loc_us-gaap_AccountsPayableCurrentAndNoncurrent_4d32d01d-0394-4080-86e7-711c69e447cb" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentIssuedPrincipal_c7bcbfe5-c19f-49f7-96d6-8758be13ac61" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentIssuedPrincipal"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_f2aa210c-4cdf-4f67-969a-fb6744850c27" xlink:to="loc_us-gaap_DebtInstrumentIssuedPrincipal_c7bcbfe5-c19f-49f7-96d6-8758be13ac61" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfLongTermDebt_e3c32562-f719-4f47-968c-842ac3c19c42" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProceedsFromIssuanceOfLongTermDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_f2aa210c-4cdf-4f67-969a-fb6744850c27" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfLongTermDebt_e3c32562-f719-4f47-968c-842ac3c19c42" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RepaymentsOfDebt_41cd7b29-8811-4142-830f-f1350b2ccb15" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RepaymentsOfDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_f2aa210c-4cdf-4f67-969a-fb6744850c27" xlink:to="loc_us-gaap_RepaymentsOfDebt_41cd7b29-8811-4142-830f-f1350b2ccb15" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_dbb9fccb-7ca2-460c-9220-f1919bc4e6a5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_f2aa210c-4cdf-4f67-969a-fb6744850c27" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_dbb9fccb-7ca2-460c-9220-f1919bc4e6a5" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTerm_32d5f258-193f-4cbd-8c25-3b63159c9321" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_f2aa210c-4cdf-4f67-969a-fb6744850c27" xlink:to="loc_us-gaap_DebtInstrumentTerm_32d5f258-193f-4cbd-8c25-3b63159c9321" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherShortTermBorrowings_0c5c3adf-5943-4d70-8008-fd5c911d1daa" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherShortTermBorrowings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_f2aa210c-4cdf-4f67-969a-fb6744850c27" xlink:to="loc_us-gaap_OtherShortTermBorrowings_0c5c3adf-5943-4d70-8008-fd5c911d1daa" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromOtherDeposits_08d5c839-db81-43bf-9e33-27cc495257aa" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProceedsFromOtherDeposits"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_f2aa210c-4cdf-4f67-969a-fb6744850c27" xlink:to="loc_us-gaap_ProceedsFromOtherDeposits_08d5c839-db81-43bf-9e33-27cc495257aa" xlink:type="arc" order="19"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cardinal.com/role/CommitmentsContingentLiabilitiesandLitigationDetails" xlink:type="simple" xlink:href="cah-20241231.xsd#CommitmentsContingentLiabilitiesandLitigationDetails"/>
  <link:definitionLink xlink:role="http://www.cardinal.com/role/CommitmentsContingentLiabilitiesandLitigationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingenciesLineItems_2e05bc8b-66a7-42d8-9d79-258c65973254" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LossContingenciesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingenciesTable_707231d8-5dac-4656-9b34-a587c435381e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LossContingenciesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LossContingenciesLineItems_2e05bc8b-66a7-42d8-9d79-258c65973254" xlink:to="loc_us-gaap_LossContingenciesTable_707231d8-5dac-4656-9b34-a587c435381e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MajorCustomersAxis_4af16073-520f-4fa6-8e45-55459ec1abd5" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MajorCustomersAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_707231d8-5dac-4656-9b34-a587c435381e" xlink:to="loc_srt_MajorCustomersAxis_4af16073-520f-4fa6-8e45-55459ec1abd5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_4af16073-520f-4fa6-8e45-55459ec1abd5_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MajorCustomersAxis_4af16073-520f-4fa6-8e45-55459ec1abd5" xlink:to="loc_srt_NameOfMajorCustomerDomain_4af16073-520f-4fa6-8e45-55459ec1abd5_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_cb76adee-6a00-4521-9d21-aea778a25bfd" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MajorCustomersAxis_4af16073-520f-4fa6-8e45-55459ec1abd5" xlink:to="loc_srt_NameOfMajorCustomerDomain_cb76adee-6a00-4521-9d21-aea778a25bfd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_CVSHealthMember_7fca2f4d-9fb0-43e3-8d0e-07f1fe9dae0a" xlink:href="cah-20241231.xsd#cah_CVSHealthMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_cb76adee-6a00-4521-9d21-aea778a25bfd" xlink:to="loc_cah_CVSHealthMember_7fca2f4d-9fb0-43e3-8d0e-07f1fe9dae0a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_LitigationCaseAxis_97a82915-5e28-496e-881e-510e6b6ffdcc" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_LitigationCaseAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_707231d8-5dac-4656-9b34-a587c435381e" xlink:to="loc_srt_LitigationCaseAxis_97a82915-5e28-496e-881e-510e6b6ffdcc" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_LitigationCaseTypeDomain_97a82915-5e28-496e-881e-510e6b6ffdcc_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_LitigationCaseTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_LitigationCaseAxis_97a82915-5e28-496e-881e-510e6b6ffdcc" xlink:to="loc_srt_LitigationCaseTypeDomain_97a82915-5e28-496e-881e-510e6b6ffdcc_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_LitigationCaseTypeDomain_5d9fe962-c5fb-402a-b666-50cfc29ad03a" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_LitigationCaseTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_LitigationCaseAxis_97a82915-5e28-496e-881e-510e6b6ffdcc" xlink:to="loc_srt_LitigationCaseTypeDomain_5d9fe962-c5fb-402a-b666-50cfc29ad03a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_NewYorkOpioidStewardshipActMember_1dddbde5-bed9-4bc5-9f29-e8f4959d1532" xlink:href="cah-20241231.xsd#cah_NewYorkOpioidStewardshipActMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_LitigationCaseTypeDomain_5d9fe962-c5fb-402a-b666-50cfc29ad03a" xlink:to="loc_cah_NewYorkOpioidStewardshipActMember_1dddbde5-bed9-4bc5-9f29-e8f4959d1532" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_OpioidLawsuitsMember_c9fbc1ca-a6b8-47c1-ac0b-c0e517afbbd3" xlink:href="cah-20241231.xsd#cah_OpioidLawsuitsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_LitigationCaseTypeDomain_5d9fe962-c5fb-402a-b666-50cfc29ad03a" xlink:to="loc_cah_OpioidLawsuitsMember_c9fbc1ca-a6b8-47c1-ac0b-c0e517afbbd3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_ProductLiabilityLawsuitsMember_b98d8279-5bb2-4329-b7b8-ea1fe93c969a" xlink:href="cah-20241231.xsd#cah_ProductLiabilityLawsuitsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_LitigationCaseTypeDomain_5d9fe962-c5fb-402a-b666-50cfc29ad03a" xlink:to="loc_cah_ProductLiabilityLawsuitsMember_b98d8279-5bb2-4329-b7b8-ea1fe93c969a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_OpioidLitigationAxis_f9d6318f-5b17-4d79-b851-2af404923f50" xlink:href="cah-20241231.xsd#cah_OpioidLitigationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_707231d8-5dac-4656-9b34-a587c435381e" xlink:to="loc_cah_OpioidLitigationAxis_f9d6318f-5b17-4d79-b851-2af404923f50" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_OpioidLitigationDomain_f9d6318f-5b17-4d79-b851-2af404923f50_default" xlink:href="cah-20241231.xsd#cah_OpioidLitigationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_cah_OpioidLitigationAxis_f9d6318f-5b17-4d79-b851-2af404923f50" xlink:to="loc_cah_OpioidLitigationDomain_f9d6318f-5b17-4d79-b851-2af404923f50_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_OpioidLitigationDomain_9ef5aefd-efd1-4d28-9518-4f7c63ecf971" xlink:href="cah-20241231.xsd#cah_OpioidLitigationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_cah_OpioidLitigationAxis_f9d6318f-5b17-4d79-b851-2af404923f50" xlink:to="loc_cah_OpioidLitigationDomain_9ef5aefd-efd1-4d28-9518-4f7c63ecf971" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_TotalOpioidLitigationMember_0c38bbf2-4e34-4458-8006-31c839207d9c" xlink:href="cah-20241231.xsd#cah_TotalOpioidLitigationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_cah_OpioidLitigationDomain_9ef5aefd-efd1-4d28-9518-4f7c63ecf971" xlink:to="loc_cah_TotalOpioidLitigationMember_0c38bbf2-4e34-4458-8006-31c839207d9c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_LawsuitTypeAxis_1a7331b1-eb87-4433-adc2-574d293d17fa" xlink:href="cah-20241231.xsd#cah_LawsuitTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_707231d8-5dac-4656-9b34-a587c435381e" xlink:to="loc_cah_LawsuitTypeAxis_1a7331b1-eb87-4433-adc2-574d293d17fa" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_LawsuitTypeDomain_1a7331b1-eb87-4433-adc2-574d293d17fa_default" xlink:href="cah-20241231.xsd#cah_LawsuitTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_cah_LawsuitTypeAxis_1a7331b1-eb87-4433-adc2-574d293d17fa" xlink:to="loc_cah_LawsuitTypeDomain_1a7331b1-eb87-4433-adc2-574d293d17fa_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_LawsuitTypeDomain_381e8858-8adc-4da1-b965-1ffc1c5de008" xlink:href="cah-20241231.xsd#cah_LawsuitTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_cah_LawsuitTypeAxis_1a7331b1-eb87-4433-adc2-574d293d17fa" xlink:to="loc_cah_LawsuitTypeDomain_381e8858-8adc-4da1-b965-1ffc1c5de008" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_ClassActionLawsuitsMember_94e1a56b-1582-4267-ae93-93407aceeb79" xlink:href="cah-20241231.xsd#cah_ClassActionLawsuitsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_cah_LawsuitTypeDomain_381e8858-8adc-4da1-b965-1ffc1c5de008" xlink:to="loc_cah_ClassActionLawsuitsMember_94e1a56b-1582-4267-ae93-93407aceeb79" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_ProductLiabilityLawsuitsMember_dd6994b8-50f2-47b7-b06c-0dae2174b6d5" xlink:href="cah-20241231.xsd#cah_ProductLiabilityLawsuitsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_cah_LawsuitTypeDomain_381e8858-8adc-4da1-b965-1ffc1c5de008" xlink:to="loc_cah_ProductLiabilityLawsuitsMember_dd6994b8-50f2-47b7-b06c-0dae2174b6d5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_PlaintiffTypeAxis_2c12820f-90b9-4fd0-9585-a9bbfd09926e" xlink:href="cah-20241231.xsd#cah_PlaintiffTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_707231d8-5dac-4656-9b34-a587c435381e" xlink:to="loc_cah_PlaintiffTypeAxis_2c12820f-90b9-4fd0-9585-a9bbfd09926e" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_PlaintiffTypeDomain_2c12820f-90b9-4fd0-9585-a9bbfd09926e_default" xlink:href="cah-20241231.xsd#cah_PlaintiffTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_cah_PlaintiffTypeAxis_2c12820f-90b9-4fd0-9585-a9bbfd09926e" xlink:to="loc_cah_PlaintiffTypeDomain_2c12820f-90b9-4fd0-9585-a9bbfd09926e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_PlaintiffTypeDomain_4d8d89cb-f4ee-4a20-9eed-d1546f9eeb46" xlink:href="cah-20241231.xsd#cah_PlaintiffTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_cah_PlaintiffTypeAxis_2c12820f-90b9-4fd0-9585-a9bbfd09926e" xlink:to="loc_cah_PlaintiffTypeDomain_4d8d89cb-f4ee-4a20-9eed-d1546f9eeb46" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_PrivatePartiesMember_10501a68-d846-4a6b-9792-007426723255" xlink:href="cah-20241231.xsd#cah_PrivatePartiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_cah_PlaintiffTypeDomain_4d8d89cb-f4ee-4a20-9eed-d1546f9eeb46" xlink:to="loc_cah_PrivatePartiesMember_10501a68-d846-4a6b-9792-007426723255" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_b13a4398-f3e1-4bf8-b512-501fe82c8690" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_707231d8-5dac-4656-9b34-a587c435381e" xlink:to="loc_srt_StatementGeographicalAxis_b13a4398-f3e1-4bf8-b512-501fe82c8690" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_b13a4398-f3e1-4bf8-b512-501fe82c8690_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_b13a4398-f3e1-4bf8-b512-501fe82c8690" xlink:to="loc_srt_SegmentGeographicalDomain_b13a4398-f3e1-4bf8-b512-501fe82c8690_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_62aa85b9-0ebe-49fc-bb0f-4561e4c3c7a9" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_b13a4398-f3e1-4bf8-b512-501fe82c8690" xlink:to="loc_srt_SegmentGeographicalDomain_62aa85b9-0ebe-49fc-bb0f-4561e4c3c7a9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_stpr_WV_de2ef08d-4017-4efd-b9b1-8d0db58e8a04" xlink:href="https://xbrl.sec.gov/stpr/2024/stpr-2024.xsd#stpr_WV"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_62aa85b9-0ebe-49fc-bb0f-4561e4c3c7a9" xlink:to="loc_stpr_WV_de2ef08d-4017-4efd-b9b1-8d0db58e8a04" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_stpr_AL_df5c9c3b-857f-45ad-a215-099f7cf2dd87" xlink:href="https://xbrl.sec.gov/stpr/2024/stpr-2024.xsd#stpr_AL"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_62aa85b9-0ebe-49fc-bb0f-4561e4c3c7a9" xlink:to="loc_stpr_AL_df5c9c3b-857f-45ad-a215-099f7cf2dd87" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_NativeAmericanTribesMember_6b4c9f48-1bd1-4772-97e1-4740ef46b8f1" xlink:href="cah-20241231.xsd#cah_NativeAmericanTribesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_62aa85b9-0ebe-49fc-bb0f-4561e4c3c7a9" xlink:to="loc_cah_NativeAmericanTribesMember_6b4c9f48-1bd1-4772-97e1-4740ef46b8f1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_CityOfBaltimoreMember_7b6bd007-275c-415c-85b7-eacacea4156f" xlink:href="cah-20241231.xsd#cah_CityOfBaltimoreMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_62aa85b9-0ebe-49fc-bb0f-4561e4c3c7a9" xlink:to="loc_cah_CityOfBaltimoreMember_7b6bd007-275c-415c-85b7-eacacea4156f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_7e89daef-319f-4f55-837a-d5572b83cbe1" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_707231d8-5dac-4656-9b34-a587c435381e" xlink:to="loc_srt_RangeAxis_7e89daef-319f-4f55-837a-d5572b83cbe1" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_7e89daef-319f-4f55-837a-d5572b83cbe1_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_7e89daef-319f-4f55-837a-d5572b83cbe1" xlink:to="loc_srt_RangeMember_7e89daef-319f-4f55-837a-d5572b83cbe1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_b6dd6341-ffec-48bb-8e7c-ec6a065738d5" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_7e89daef-319f-4f55-837a-d5572b83cbe1" xlink:to="loc_srt_RangeMember_b6dd6341-ffec-48bb-8e7c-ec6a065738d5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_2565e71e-2b83-4fba-a3b1-45478c6bf9f0" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_b6dd6341-ffec-48bb-8e7c-ec6a065738d5" xlink:to="loc_srt_MinimumMember_2565e71e-2b83-4fba-a3b1-45478c6bf9f0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_18c42132-5656-456c-b5b2-eebc2264e10e" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_b6dd6341-ffec-48bb-8e7c-ec6a065738d5" xlink:to="loc_srt_MaximumMember_18c42132-5656-456c-b5b2-eebc2264e10e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingenciesByNatureOfContingencyAxis_eea9db9c-c0fe-4025-89b9-b60b0700fcad" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LossContingenciesByNatureOfContingencyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_707231d8-5dac-4656-9b34-a587c435381e" xlink:to="loc_us-gaap_LossContingenciesByNatureOfContingencyAxis_eea9db9c-c0fe-4025-89b9-b60b0700fcad" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingencyNatureDomain_eea9db9c-c0fe-4025-89b9-b60b0700fcad_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LossContingencyNatureDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LossContingenciesByNatureOfContingencyAxis_eea9db9c-c0fe-4025-89b9-b60b0700fcad" xlink:to="loc_us-gaap_LossContingencyNatureDomain_eea9db9c-c0fe-4025-89b9-b60b0700fcad_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingencyNatureDomain_453c2f45-e358-441e-8aa5-21980174878b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LossContingencyNatureDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LossContingenciesByNatureOfContingencyAxis_eea9db9c-c0fe-4025-89b9-b60b0700fcad" xlink:to="loc_us-gaap_LossContingencyNatureDomain_453c2f45-e358-441e-8aa5-21980174878b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_OpioidLawsuitsMember_59f120ad-4173-4f6b-9b96-6d9c77881521" xlink:href="cah-20241231.xsd#cah_OpioidLawsuitsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingencyNatureDomain_453c2f45-e358-441e-8aa5-21980174878b" xlink:to="loc_cah_OpioidLawsuitsMember_59f120ad-4173-4f6b-9b96-6d9c77881521" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_ProductLiabilityLawsuitsMember_3114118e-4cc4-49ac-ab9a-3810eb95d67e" xlink:href="cah-20241231.xsd#cah_ProductLiabilityLawsuitsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingencyNatureDomain_453c2f45-e358-441e-8aa5-21980174878b" xlink:to="loc_cah_ProductLiabilityLawsuitsMember_3114118e-4cc4-49ac-ab9a-3810eb95d67e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_3e4af352-d654-488b-a15b-f3281f756371" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsequentEventTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_707231d8-5dac-4656-9b34-a587c435381e" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_3e4af352-d654-488b-a15b-f3281f756371" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_3e4af352-d654-488b-a15b-f3281f756371_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_3e4af352-d654-488b-a15b-f3281f756371" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_3e4af352-d654-488b-a15b-f3281f756371_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_fa3393bc-4da0-462b-8146-63d29eae53c2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_3e4af352-d654-488b-a15b-f3281f756371" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_fa3393bc-4da0-462b-8146-63d29eae53c2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventMember_eb9f1484-4c23-4e82-89ea-e5f3f621eb67" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsequentEventMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_fa3393bc-4da0-462b-8146-63d29eae53c2" xlink:to="loc_us-gaap_SubsequentEventMember_eb9f1484-4c23-4e82-89ea-e5f3f621eb67" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_a397f8bf-883b-4041-8c62-37f0f6a46b6f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_707231d8-5dac-4656-9b34-a587c435381e" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_a397f8bf-883b-4041-8c62-37f0f6a46b6f" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_a397f8bf-883b-4041-8c62-37f0f6a46b6f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_a397f8bf-883b-4041-8c62-37f0f6a46b6f" xlink:to="loc_us-gaap_SegmentDomain_a397f8bf-883b-4041-8c62-37f0f6a46b6f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_35220953-e984-4b14-9d4c-5a74f8382062" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_a397f8bf-883b-4041-8c62-37f0f6a46b6f" xlink:to="loc_us-gaap_SegmentDomain_35220953-e984-4b14-9d4c-5a74f8382062" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_PharmaceuticalAndSpecialtySolutionsMember_8ce8089f-cabb-4d23-9544-33b1473bd2ce" xlink:href="cah-20241231.xsd#cah_PharmaceuticalAndSpecialtySolutionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_35220953-e984-4b14-9d4c-5a74f8382062" xlink:to="loc_cah_PharmaceuticalAndSpecialtySolutionsMember_8ce8089f-cabb-4d23-9544-33b1473bd2ce" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_AgreementsAxis_4045c6a6-30ee-4918-870b-0fdd6fe80488" xlink:href="cah-20241231.xsd#cah_AgreementsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_707231d8-5dac-4656-9b34-a587c435381e" xlink:to="loc_cah_AgreementsAxis_4045c6a6-30ee-4918-870b-0fdd6fe80488" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_AgreementsDomain_4045c6a6-30ee-4918-870b-0fdd6fe80488_default" xlink:href="cah-20241231.xsd#cah_AgreementsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_cah_AgreementsAxis_4045c6a6-30ee-4918-870b-0fdd6fe80488" xlink:to="loc_cah_AgreementsDomain_4045c6a6-30ee-4918-870b-0fdd6fe80488_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_AgreementsDomain_bf5ce97e-9d2a-46d2-b813-83cbdaae6053" xlink:href="cah-20241231.xsd#cah_AgreementsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_cah_AgreementsAxis_4045c6a6-30ee-4918-870b-0fdd6fe80488" xlink:to="loc_cah_AgreementsDomain_bf5ce97e-9d2a-46d2-b813-83cbdaae6053" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_IVCApril2023AgreementMember_9cb27c0c-f73a-45c3-bdb1-531d0d1c1f53" xlink:href="cah-20241231.xsd#cah_IVCApril2023AgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_cah_AgreementsDomain_bf5ce97e-9d2a-46d2-b813-83cbdaae6053" xlink:to="loc_cah_IVCApril2023AgreementMember_9cb27c0c-f73a-45c3-bdb1-531d0d1c1f53" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermPurchaseCommitmentPeriod_c22c6675-e239-44d7-93eb-b2a7be644257" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermPurchaseCommitmentPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_2e05bc8b-66a7-42d8-9d79-258c65973254" xlink:to="loc_us-gaap_LongtermPurchaseCommitmentPeriod_c22c6675-e239-44d7-93eb-b2a7be644257" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_AggregateAnnualAssessment_71ef5949-9b92-42ca-9af6-568c1619efd9" xlink:href="cah-20241231.xsd#cah_AggregateAnnualAssessment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_2e05bc8b-66a7-42d8-9d79-258c65973254" xlink:to="loc_cah_AggregateAnnualAssessment_71ef5949-9b92-42ca-9af6-568c1619efd9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LitigationReserve_7b1551c9-6841-4fe9-a15d-d22e8a558bf1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LitigationReserve"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_2e05bc8b-66a7-42d8-9d79-258c65973254" xlink:to="loc_us-gaap_LitigationReserve_7b1551c9-6841-4fe9-a15d-d22e8a558bf1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LitigationReserveCurrent_f478b5bd-786e-43a4-b441-29410d976d8f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LitigationReserveCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_2e05bc8b-66a7-42d8-9d79-258c65973254" xlink:to="loc_us-gaap_LitigationReserveCurrent_f478b5bd-786e-43a4-b441-29410d976d8f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LitigationSettlementLoss_15bab7d2-4879-455b-9c97-f71c313b35ef" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LitigationSettlementLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_2e05bc8b-66a7-42d8-9d79-258c65973254" xlink:to="loc_us-gaap_LitigationSettlementLoss_15bab7d2-4879-455b-9c97-f71c313b35ef" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_IncomeAsAResultOfPrepayments_1b2596e2-8ee8-4790-bf3e-c61e2d53adaa" xlink:href="cah-20241231.xsd#cah_IncomeAsAResultOfPrepayments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_2e05bc8b-66a7-42d8-9d79-258c65973254" xlink:to="loc_cah_IncomeAsAResultOfPrepayments_1b2596e2-8ee8-4790-bf3e-c61e2d53adaa" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingencyAccrualCarryingValuePeriodIncreaseDecrease_85557b9a-2c39-4b3f-ab09-e45ad42a6eb9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LossContingencyAccrualCarryingValuePeriodIncreaseDecrease"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_2e05bc8b-66a7-42d8-9d79-258c65973254" xlink:to="loc_us-gaap_LossContingencyAccrualCarryingValuePeriodIncreaseDecrease_85557b9a-2c39-4b3f-ab09-e45ad42a6eb9" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_SettlingStates_fff01cb2-492a-4bed-993b-7b15030b0f37" xlink:href="cah-20241231.xsd#cah_SettlingStates"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_2e05bc8b-66a7-42d8-9d79-258c65973254" xlink:to="loc_cah_SettlingStates_fff01cb2-492a-4bed-993b-7b15030b0f37" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_SettlingUSTerritories_d739b6d6-29eb-431c-921e-01977fd3984f" xlink:href="cah-20241231.xsd#cah_SettlingUSTerritories"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_2e05bc8b-66a7-42d8-9d79-258c65973254" xlink:to="loc_cah_SettlingUSTerritories_d739b6d6-29eb-431c-921e-01977fd3984f" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingencyEstimateOfPossibleLoss_55a09e6e-5b57-48ff-b2b0-6bec82395446" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LossContingencyEstimateOfPossibleLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_2e05bc8b-66a7-42d8-9d79-258c65973254" xlink:to="loc_us-gaap_LossContingencyEstimateOfPossibleLoss_55a09e6e-5b57-48ff-b2b0-6bec82395446" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForLegalSettlements_afe4d8e9-8f65-4600-b901-9f3c0df85acc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsForLegalSettlements"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_2e05bc8b-66a7-42d8-9d79-258c65973254" xlink:to="loc_us-gaap_PaymentsForLegalSettlements_afe4d8e9-8f65-4600-b901-9f3c0df85acc" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingencyAccrualAtCarryingValue_94a4cfc1-f0e2-4c8f-9297-a855406256b6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LossContingencyAccrualAtCarryingValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_2e05bc8b-66a7-42d8-9d79-258c65973254" xlink:to="loc_us-gaap_LossContingencyAccrualAtCarryingValue_94a4cfc1-f0e2-4c8f-9297-a855406256b6" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_LossContingencyLawsuitsNumber_16dfd401-9c7b-4d34-98b7-67720610af27" xlink:href="cah-20241231.xsd#cah_LossContingencyLawsuitsNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_2e05bc8b-66a7-42d8-9d79-258c65973254" xlink:to="loc_cah_LossContingencyLawsuitsNumber_16dfd401-9c7b-4d34-98b7-67720610af27" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InsuranceRecoveries_0915ca22-62b1-439b-b363-5606bc4f2ff2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InsuranceRecoveries"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_2e05bc8b-66a7-42d8-9d79-258c65973254" xlink:to="loc_us-gaap_InsuranceRecoveries_0915ca22-62b1-439b-b363-5606bc4f2ff2" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_IncomefromSettlementsofClassActionLawsuits_427eed4e-fb3f-47fd-8aab-efb22b628cec" xlink:href="cah-20241231.xsd#cah_IncomefromSettlementsofClassActionLawsuits"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_2e05bc8b-66a7-42d8-9d79-258c65973254" xlink:to="loc_cah_IncomefromSettlementsofClassActionLawsuits_427eed4e-fb3f-47fd-8aab-efb22b628cec" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingencyClaimsSettledNumber_0dbdb6ce-6f6a-4902-972f-b00f7db6db4b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LossContingencyClaimsSettledNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_2e05bc8b-66a7-42d8-9d79-258c65973254" xlink:to="loc_us-gaap_LossContingencyClaimsSettledNumber_0dbdb6ce-6f6a-4902-972f-b00f7db6db4b" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProductLiabilityAccrualPeriodExpense_4be1d738-4d13-478b-abfd-feebfc2a4f94" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProductLiabilityAccrualPeriodExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_2e05bc8b-66a7-42d8-9d79-258c65973254" xlink:to="loc_us-gaap_ProductLiabilityAccrualPeriodExpense_4be1d738-4d13-478b-abfd-feebfc2a4f94" xlink:type="arc" order="16"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cardinal.com/role/IncomeTaxesNarrativeDetails" xlink:type="simple" xlink:href="cah-20241231.xsd#IncomeTaxesNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.cardinal.com/role/IncomeTaxesNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxCreditCarryforwardLineItems_aa2ed5a7-ca8e-4091-8d39-77a7c4fdc24c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TaxCreditCarryforwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxCreditCarryforwardTable_cb140f85-faf3-481a-9749-d1cb49e29dea" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TaxCreditCarryforwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_TaxCreditCarryforwardLineItems_aa2ed5a7-ca8e-4091-8d39-77a7c4fdc24c" xlink:to="loc_us-gaap_TaxCreditCarryforwardTable_cb140f85-faf3-481a-9749-d1cb49e29dea" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_e459f5d1-f685-49a4-a70d-f68f62d7f9af" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_TaxCreditCarryforwardTable_cb140f85-faf3-481a-9749-d1cb49e29dea" xlink:to="loc_srt_RangeAxis_e459f5d1-f685-49a4-a70d-f68f62d7f9af" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_e459f5d1-f685-49a4-a70d-f68f62d7f9af_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_e459f5d1-f685-49a4-a70d-f68f62d7f9af" xlink:to="loc_srt_RangeMember_e459f5d1-f685-49a4-a70d-f68f62d7f9af_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_65d9a1bd-d73d-4517-ab1d-dd3270eca21f" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_e459f5d1-f685-49a4-a70d-f68f62d7f9af" xlink:to="loc_srt_RangeMember_65d9a1bd-d73d-4517-ab1d-dd3270eca21f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_1b9084e4-aef2-463f-a553-c419a2ce51d6" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_65d9a1bd-d73d-4517-ab1d-dd3270eca21f" xlink:to="loc_srt_MinimumMember_1b9084e4-aef2-463f-a553-c419a2ce51d6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_56ca9e0b-3135-47b5-a01a-458fbf400798" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_65d9a1bd-d73d-4517-ab1d-dd3270eca21f" xlink:to="loc_srt_MaximumMember_56ca9e0b-3135-47b5-a01a-458fbf400798" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementScenarioAxis_7bf507fc-1a08-4054-a2f4-37aca2a47dee" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_StatementScenarioAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_TaxCreditCarryforwardTable_cb140f85-faf3-481a-9749-d1cb49e29dea" xlink:to="loc_srt_StatementScenarioAxis_7bf507fc-1a08-4054-a2f4-37aca2a47dee" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioUnspecifiedDomain_7bf507fc-1a08-4054-a2f4-37aca2a47dee_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ScenarioUnspecifiedDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementScenarioAxis_7bf507fc-1a08-4054-a2f4-37aca2a47dee" xlink:to="loc_srt_ScenarioUnspecifiedDomain_7bf507fc-1a08-4054-a2f4-37aca2a47dee_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioUnspecifiedDomain_04841589-a351-4c88-b0e6-d764f50dc060" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ScenarioUnspecifiedDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementScenarioAxis_7bf507fc-1a08-4054-a2f4-37aca2a47dee" xlink:to="loc_srt_ScenarioUnspecifiedDomain_04841589-a351-4c88-b0e6-d764f50dc060" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioForecastMember_2ce4ed7e-df72-4b17-820d-938498da1a6b" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ScenarioForecastMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ScenarioUnspecifiedDomain_04841589-a351-4c88-b0e6-d764f50dc060" xlink:to="loc_srt_ScenarioForecastMember_2ce4ed7e-df72-4b17-820d-938498da1a6b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_GoodwillImpairmentAxis_ffbe4573-cb34-4d71-b4cf-3a8bed05a012" xlink:href="cah-20241231.xsd#cah_GoodwillImpairmentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_TaxCreditCarryforwardTable_cb140f85-faf3-481a-9749-d1cb49e29dea" xlink:to="loc_cah_GoodwillImpairmentAxis_ffbe4573-cb34-4d71-b4cf-3a8bed05a012" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_GoodwillImpairmentDomain_ffbe4573-cb34-4d71-b4cf-3a8bed05a012_default" xlink:href="cah-20241231.xsd#cah_GoodwillImpairmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_cah_GoodwillImpairmentAxis_ffbe4573-cb34-4d71-b4cf-3a8bed05a012" xlink:to="loc_cah_GoodwillImpairmentDomain_ffbe4573-cb34-4d71-b4cf-3a8bed05a012_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_GoodwillImpairmentDomain_72d154e4-7fd5-4166-a42c-a4ecda21f4b2" xlink:href="cah-20241231.xsd#cah_GoodwillImpairmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_cah_GoodwillImpairmentAxis_ffbe4573-cb34-4d71-b4cf-3a8bed05a012" xlink:to="loc_cah_GoodwillImpairmentDomain_72d154e4-7fd5-4166-a42c-a4ecda21f4b2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_GMPDMember_726811de-91d9-473b-9c8d-c3ebf43dc358" xlink:href="cah-20241231.xsd#cah_GMPDMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_cah_GoodwillImpairmentDomain_72d154e4-7fd5-4166-a42c-a4ecda21f4b2" xlink:to="loc_cah_GMPDMember_726811de-91d9-473b-9c8d-c3ebf43dc358" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_1614ac37-625c-4a04-9764-ba5ddf70cffa" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsequentEventTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_TaxCreditCarryforwardTable_cb140f85-faf3-481a-9749-d1cb49e29dea" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_1614ac37-625c-4a04-9764-ba5ddf70cffa" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_1614ac37-625c-4a04-9764-ba5ddf70cffa_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_1614ac37-625c-4a04-9764-ba5ddf70cffa" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_1614ac37-625c-4a04-9764-ba5ddf70cffa_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_41319722-7156-4953-9b2f-e8e97494932e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_1614ac37-625c-4a04-9764-ba5ddf70cffa" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_41319722-7156-4953-9b2f-e8e97494932e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventMember_ba4e9dfe-35ce-4c93-8b58-5524883a4315" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsequentEventMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_41319722-7156-4953-9b2f-e8e97494932e" xlink:to="loc_us-gaap_SubsequentEventMember_ba4e9dfe-35ce-4c93-8b58-5524883a4315" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_0c269747-e427-44b8-972d-908f4f469c32" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EffectiveIncomeTaxRateContinuingOperations"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TaxCreditCarryforwardLineItems_aa2ed5a7-ca8e-4091-8d39-77a7c4fdc24c" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_0c269747-e427-44b8-972d-908f4f469c32" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillImpairmentLoss_37736300-71a9-43e1-b89c-4c37af02b1d7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GoodwillImpairmentLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TaxCreditCarryforwardLineItems_aa2ed5a7-ca8e-4091-8d39-77a7c4fdc24c" xlink:to="loc_us-gaap_GoodwillImpairmentLoss_37736300-71a9-43e1-b89c-4c37af02b1d7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_33be76db-dbf8-427b-bada-11ebabe74479" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TaxCreditCarryforwardLineItems_aa2ed5a7-ca8e-4091-8d39-77a7c4fdc24c" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_33be76db-dbf8-427b-bada-11ebabe74479" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrecognizedTaxBenefits_fddb2ef8-63b6-4555-b658-bff2875dc8fa" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_UnrecognizedTaxBenefits"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TaxCreditCarryforwardLineItems_aa2ed5a7-ca8e-4091-8d39-77a7c4fdc24c" xlink:to="loc_us-gaap_UnrecognizedTaxBenefits_fddb2ef8-63b6-4555-b658-bff2875dc8fa" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate_ab94ce73-5d61-4412-b4fa-8877e195d6be" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TaxCreditCarryforwardLineItems_aa2ed5a7-ca8e-4091-8d39-77a7c4fdc24c" xlink:to="loc_us-gaap_UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate_ab94ce73-5d61-4412-b4fa-8877e195d6be" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued_63bd2576-75a5-48df-bba2-ad1d5e2b1ed2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TaxCreditCarryforwardLineItems_aa2ed5a7-ca8e-4091-8d39-77a7c4fdc24c" xlink:to="loc_us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued_63bd2576-75a5-48df-bba2-ad1d5e2b1ed2" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DecreaseInUnrecognizedTaxBenefitsIsReasonablyPossible_fb8d2534-6641-4818-9ff3-90760d8c2dac" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DecreaseInUnrecognizedTaxBenefitsIsReasonablyPossible"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TaxCreditCarryforwardLineItems_aa2ed5a7-ca8e-4091-8d39-77a7c4fdc24c" xlink:to="loc_us-gaap_DecreaseInUnrecognizedTaxBenefitsIsReasonablyPossible_fb8d2534-6641-4818-9ff3-90760d8c2dac" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cardinal.com/role/FairValueMeasurementsFairValueofAssetsandLiabilitiesMeasuredonaRecurringBasisDetails" xlink:type="simple" xlink:href="cah-20241231.xsd#FairValueMeasurementsFairValueofAssetsandLiabilitiesMeasuredonaRecurringBasisDetails"/>
  <link:definitionLink xlink:role="http://www.cardinal.com/role/FairValueMeasurementsFairValueofAssetsandLiabilitiesMeasuredonaRecurringBasisDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_0d8a4e80-ce6e-4665-86bc-75504c500331" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_61106f63-d559-4139-8b5f-ebb3553bf54c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_0d8a4e80-ce6e-4665-86bc-75504c500331" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_61106f63-d559-4139-8b5f-ebb3553bf54c" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_7ab76d3d-a229-45e5-b967-39fc797d2b37" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_61106f63-d559-4139-8b5f-ebb3553bf54c" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_7ab76d3d-a229-45e5-b967-39fc797d2b37" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_7ab76d3d-a229-45e5-b967-39fc797d2b37_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_7ab76d3d-a229-45e5-b967-39fc797d2b37" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_7ab76d3d-a229-45e5-b967-39fc797d2b37_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_2d498836-3315-44ca-ae34-5de533a9139c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_7ab76d3d-a229-45e5-b967-39fc797d2b37" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_2d498836-3315-44ca-ae34-5de533a9139c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel1Member_e172d07e-daf1-4bd3-81d1-a88e77d5e672" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueInputsLevel1Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_2d498836-3315-44ca-ae34-5de533a9139c" xlink:to="loc_us-gaap_FairValueInputsLevel1Member_e172d07e-daf1-4bd3-81d1-a88e77d5e672" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_133ecb71-d053-47a9-ba58-6bf596bec645" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueInputsLevel2Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_2d498836-3315-44ca-ae34-5de533a9139c" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_133ecb71-d053-47a9-ba58-6bf596bec645" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_76988212-ca6b-4735-84fc-6b31e7073b49" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_2d498836-3315-44ca-ae34-5de533a9139c" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_76988212-ca6b-4735-84fc-6b31e7073b49" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByMeasurementFrequencyAxis_bf13f82f-c972-4b72-9517-33d4cb49d6c0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueByMeasurementFrequencyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_61106f63-d559-4139-8b5f-ebb3553bf54c" xlink:to="loc_us-gaap_FairValueByMeasurementFrequencyAxis_bf13f82f-c972-4b72-9517-33d4cb49d6c0" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_bf13f82f-c972-4b72-9517-33d4cb49d6c0_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_bf13f82f-c972-4b72-9517-33d4cb49d6c0" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_bf13f82f-c972-4b72-9517-33d4cb49d6c0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_fd86bfaf-800b-41ab-9074-0c90561e0868" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_bf13f82f-c972-4b72-9517-33d4cb49d6c0" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_fd86bfaf-800b-41ab-9074-0c90561e0868" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsRecurringMember_8f5c2ac2-e097-4858-ad55-965c5b78b45a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementsRecurringMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementFrequencyDomain_fd86bfaf-800b-41ab-9074-0c90561e0868" xlink:to="loc_us-gaap_FairValueMeasurementsRecurringMember_8f5c2ac2-e097-4858-ad55-965c5b78b45a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsNonrecurringMember_7a00b08d-24eb-4a64-b0c2-d54e3bdf79bc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementsNonrecurringMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementFrequencyDomain_fd86bfaf-800b-41ab-9074-0c90561e0868" xlink:to="loc_us-gaap_FairValueMeasurementsNonrecurringMember_7a00b08d-24eb-4a64-b0c2-d54e3bdf79bc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_a08196ec-debb-43be-999d-10b3167ae584" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_61106f63-d559-4139-8b5f-ebb3553bf54c" xlink:to="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_a08196ec-debb-43be-999d-10b3167ae584" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_a08196ec-debb-43be-999d-10b3167ae584_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_a08196ec-debb-43be-999d-10b3167ae584" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_a08196ec-debb-43be-999d-10b3167ae584_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_4c691025-a44f-47d8-85e8-09d026f488d6" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_a08196ec-debb-43be-999d-10b3167ae584" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_4c691025-a44f-47d8-85e8-09d026f488d6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_TransactionDataSystemInvestmentMember_1d147ec0-4aab-4363-91d0-af812d6bced5" xlink:href="cah-20241231.xsd#cah_TransactionDataSystemInvestmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_4c691025-a44f-47d8-85e8-09d026f488d6" xlink:to="loc_cah_TransactionDataSystemInvestmentMember_1d147ec0-4aab-4363-91d0-af812d6bced5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosureAbstract_387b2b59-5d6a-4b1f-83be-c42c6c3bc0f9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AssetsFairValueDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_0d8a4e80-ce6e-4665-86bc-75504c500331" xlink:to="loc_us-gaap_AssetsFairValueDisclosureAbstract_387b2b59-5d6a-4b1f-83be-c42c6c3bc0f9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure_b07e91c5-60e4-4de3-af5e-c68b57b97722" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CashAndCashEquivalentsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_387b2b59-5d6a-4b1f-83be-c42c6c3bc0f9" xlink:to="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure_b07e91c5-60e4-4de3-af5e-c68b57b97722" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentsFairValueDisclosure_cada162d-6667-4e42-890f-2475bd28522a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_387b2b59-5d6a-4b1f-83be-c42c6c3bc0f9" xlink:to="loc_us-gaap_InvestmentsFairValueDisclosure_cada162d-6667-4e42-890f-2475bd28522a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetsLiabilitiesAtFairValueNet_255acc90-9192-467e-90da-f3a5765de20a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeAssetsLiabilitiesAtFairValueNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_387b2b59-5d6a-4b1f-83be-c42c6c3bc0f9" xlink:to="loc_us-gaap_DerivativeAssetsLiabilitiesAtFairValueNet_255acc90-9192-467e-90da-f3a5765de20a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestmentOwnershipPercentage_4117447a-4620-4e8e-997e-9037782be8b6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EquityMethodInvestmentOwnershipPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_387b2b59-5d6a-4b1f-83be-c42c6c3bc0f9" xlink:to="loc_us-gaap_EquityMethodInvestmentOwnershipPercentage_4117447a-4620-4e8e-997e-9037782be8b6" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestmentsFairValueDisclosure_5b33e6d5-c33c-4936-bdd7-7ab861804619" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EquityMethodInvestmentsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_387b2b59-5d6a-4b1f-83be-c42c6c3bc0f9" xlink:to="loc_us-gaap_EquityMethodInvestmentsFairValueDisclosure_5b33e6d5-c33c-4936-bdd7-7ab861804619" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesAbstract_4c067222-3b11-4e43-bcbf-14d9ed12dadb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilitiesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_0d8a4e80-ce6e-4665-86bc-75504c500331" xlink:to="loc_us-gaap_LiabilitiesAbstract_4c067222-3b11-4e43-bcbf-14d9ed12dadb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetsLiabilitiesAtFairValueNet_bf891296-c0fa-460d-ab97-86bb9eec20ea" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeAssetsLiabilitiesAtFairValueNet"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cardinal.com/role/FinancialInstrumentsNarrativeDetails" xlink:type="simple" xlink:href="cah-20241231.xsd#FinancialInstrumentsNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.cardinal.com/role/FinancialInstrumentsNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLineItems_6fa4cefe-c4c6-45ff-9106-cb80a00560f0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeTable_71f62344-17f2-42cb-81d3-bdb94309817a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeLineItems_6fa4cefe-c4c6-45ff-9106-cb80a00560f0" xlink:to="loc_us-gaap_DerivativeTable_71f62344-17f2-42cb-81d3-bdb94309817a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationAxis_b4aaaf05-4a30-4daf-9d8d-5373fb8e2c79" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementLocationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_71f62344-17f2-42cb-81d3-bdb94309817a" xlink:to="loc_us-gaap_IncomeStatementLocationAxis_b4aaaf05-4a30-4daf-9d8d-5373fb8e2c79" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_b4aaaf05-4a30-4daf-9d8d-5373fb8e2c79_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_b4aaaf05-4a30-4daf-9d8d-5373fb8e2c79" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_b4aaaf05-4a30-4daf-9d8d-5373fb8e2c79_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_bc5de1ab-90e3-4b9d-8532-f0c7d4b072b8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_b4aaaf05-4a30-4daf-9d8d-5373fb8e2c79" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_bc5de1ab-90e3-4b9d-8532-f0c7d4b072b8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpenseMember_c0da21c2-d3ab-49bd-89bd-f09ff4436b0b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherNonoperatingIncomeExpenseMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_bc5de1ab-90e3-4b9d-8532-f0c7d4b072b8" xlink:to="loc_us-gaap_OtherNonoperatingIncomeExpenseMember_c0da21c2-d3ab-49bd-89bd-f09ff4436b0b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_df40f168-7d79-4d0f-805f-30e2c5ce5812" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_71f62344-17f2-42cb-81d3-bdb94309817a" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_df40f168-7d79-4d0f-805f-30e2c5ce5812" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_df40f168-7d79-4d0f-805f-30e2c5ce5812_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_df40f168-7d79-4d0f-805f-30e2c5ce5812" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_df40f168-7d79-4d0f-805f-30e2c5ce5812_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_465c0048-787e-4ae6-b142-1043a6b6b272" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_df40f168-7d79-4d0f-805f-30e2c5ce5812" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_465c0048-787e-4ae6-b142-1043a6b6b272" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_c83898af-4c23-4359-97cb-2a730e91e5bc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueInputsLevel2Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_465c0048-787e-4ae6-b142-1043a6b6b272" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_c83898af-4c23-4359-97cb-2a730e91e5bc" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationAxis_5fd55f9e-6b22-4e4c-a8f9-5a972d440292" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_HedgingDesignationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_71f62344-17f2-42cb-81d3-bdb94309817a" xlink:to="loc_us-gaap_HedgingDesignationAxis_5fd55f9e-6b22-4e4c-a8f9-5a972d440292" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_5fd55f9e-6b22-4e4c-a8f9-5a972d440292_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_HedgingDesignationAxis_5fd55f9e-6b22-4e4c-a8f9-5a972d440292" xlink:to="loc_us-gaap_HedgingDesignationDomain_5fd55f9e-6b22-4e4c-a8f9-5a972d440292_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_4db55954-fe72-4af7-8a32-b5a78d28a9dc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_HedgingDesignationAxis_5fd55f9e-6b22-4e4c-a8f9-5a972d440292" xlink:to="loc_us-gaap_HedgingDesignationDomain_4db55954-fe72-4af7-8a32-b5a78d28a9dc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DesignatedAsHedgingInstrumentMember_5947c2c7-c7f0-4bb1-bede-156d2f3ec611" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DesignatedAsHedgingInstrumentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_4db55954-fe72-4af7-8a32-b5a78d28a9dc" xlink:to="loc_us-gaap_DesignatedAsHedgingInstrumentMember_5947c2c7-c7f0-4bb1-bede-156d2f3ec611" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NondesignatedMember_dc639b39-c4ab-4011-8cdd-f9b2cf179908" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NondesignatedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_4db55954-fe72-4af7-8a32-b5a78d28a9dc" xlink:to="loc_us-gaap_NondesignatedMember_dc639b39-c4ab-4011-8cdd-f9b2cf179908" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_9a7246f1-0ce2-4b76-aa00-9f8ab87b104a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_71f62344-17f2-42cb-81d3-bdb94309817a" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_9a7246f1-0ce2-4b76-aa00-9f8ab87b104a" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_9a7246f1-0ce2-4b76-aa00-9f8ab87b104a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_9a7246f1-0ce2-4b76-aa00-9f8ab87b104a" xlink:to="loc_us-gaap_HedgingRelationshipDomain_9a7246f1-0ce2-4b76-aa00-9f8ab87b104a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_34a7fcfc-b3a0-46a0-9cc4-a18b1d7bee1c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_9a7246f1-0ce2-4b76-aa00-9f8ab87b104a" xlink:to="loc_us-gaap_HedgingRelationshipDomain_34a7fcfc-b3a0-46a0-9cc4-a18b1d7bee1c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueHedgingMember_c574d23f-ef91-416b-9220-265d2ef99a1d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueHedgingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingRelationshipDomain_34a7fcfc-b3a0-46a0-9cc4-a18b1d7bee1c" xlink:to="loc_us-gaap_FairValueHedgingMember_c574d23f-ef91-416b-9220-265d2ef99a1d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashFlowHedgingMember_1090b282-70c4-405f-9644-110dcc224dcb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CashFlowHedgingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingRelationshipDomain_34a7fcfc-b3a0-46a0-9cc4-a18b1d7bee1c" xlink:to="loc_us-gaap_CashFlowHedgingMember_1090b282-70c4-405f-9644-110dcc224dcb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetInvestmentHedgingMember_5bf3235c-4582-4a85-bec1-44388a73c795" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetInvestmentHedgingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingRelationshipDomain_34a7fcfc-b3a0-46a0-9cc4-a18b1d7bee1c" xlink:to="loc_us-gaap_NetInvestmentHedgingMember_5bf3235c-4582-4a85-bec1-44388a73c795" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_ea5f963d-6c51-496c-8a36-84eeb21185c1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_71f62344-17f2-42cb-81d3-bdb94309817a" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_ea5f963d-6c51-496c-8a36-84eeb21185c1" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_ea5f963d-6c51-496c-8a36-84eeb21185c1_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_ea5f963d-6c51-496c-8a36-84eeb21185c1" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_ea5f963d-6c51-496c-8a36-84eeb21185c1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_39a9b2d1-d242-4f57-9d82-a04e5a26a226" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_ea5f963d-6c51-496c-8a36-84eeb21185c1" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_39a9b2d1-d242-4f57-9d82-a04e5a26a226" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashFlowHedgingMember_e6540cb8-b715-4a21-ac3d-3ec189af1607" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CashFlowHedgingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_39a9b2d1-d242-4f57-9d82-a04e5a26a226" xlink:to="loc_us-gaap_CashFlowHedgingMember_e6540cb8-b715-4a21-ac3d-3ec189af1607" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeContractMember_98489a38-0c40-40bc-8be8-79a115bb3148" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ForeignExchangeContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_39a9b2d1-d242-4f57-9d82-a04e5a26a226" xlink:to="loc_us-gaap_ForeignExchangeContractMember_98489a38-0c40-40bc-8be8-79a115bb3148" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateSwapMember_fc667fbc-5150-48c4-8f5e-5e3d087c738a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestRateSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_39a9b2d1-d242-4f57-9d82-a04e5a26a226" xlink:to="loc_us-gaap_InterestRateSwapMember_fc667fbc-5150-48c4-8f5e-5e3d087c738a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CurrencySwapMember_c544bb68-b2ce-46da-ac20-39e1ac42358f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CurrencySwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_39a9b2d1-d242-4f57-9d82-a04e5a26a226" xlink:to="loc_us-gaap_CurrencySwapMember_c544bb68-b2ce-46da-ac20-39e1ac42358f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_MaturityDateAxis_72c85a6b-17a9-4469-a8cd-a680d6fbdc42" xlink:href="cah-20241231.xsd#cah_MaturityDateAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_71f62344-17f2-42cb-81d3-bdb94309817a" xlink:to="loc_cah_MaturityDateAxis_72c85a6b-17a9-4469-a8cd-a680d6fbdc42" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_MaturityDateDomain_72c85a6b-17a9-4469-a8cd-a680d6fbdc42_default" xlink:href="cah-20241231.xsd#cah_MaturityDateDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_cah_MaturityDateAxis_72c85a6b-17a9-4469-a8cd-a680d6fbdc42" xlink:to="loc_cah_MaturityDateDomain_72c85a6b-17a9-4469-a8cd-a680d6fbdc42_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_MaturityDateDomain_3704779f-f36a-48ac-81ca-d2b25cf1e416" xlink:href="cah-20241231.xsd#cah_MaturityDateDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_cah_MaturityDateAxis_72c85a6b-17a9-4469-a8cd-a680d6fbdc42" xlink:to="loc_cah_MaturityDateDomain_3704779f-f36a-48ac-81ca-d2b25cf1e416" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_September2025Member_cbf64de2-75dc-4849-9852-1b4b9e63f905" xlink:href="cah-20241231.xsd#cah_September2025Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_cah_MaturityDateDomain_3704779f-f36a-48ac-81ca-d2b25cf1e416" xlink:to="loc_cah_September2025Member_cbf64de2-75dc-4849-9852-1b4b9e63f905" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_June2027Member_bf7d2bbb-2fe9-4e8e-8eda-9a78fef873a7" xlink:href="cah-20241231.xsd#cah_June2027Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_cah_MaturityDateDomain_3704779f-f36a-48ac-81ca-d2b25cf1e416" xlink:to="loc_cah_June2027Member_bf7d2bbb-2fe9-4e8e-8eda-9a78fef873a7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementScenarioAxis_6376d13a-f419-4461-a6be-6d15524b7ace" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_StatementScenarioAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_71f62344-17f2-42cb-81d3-bdb94309817a" xlink:to="loc_srt_StatementScenarioAxis_6376d13a-f419-4461-a6be-6d15524b7ace" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioUnspecifiedDomain_6376d13a-f419-4461-a6be-6d15524b7ace_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ScenarioUnspecifiedDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementScenarioAxis_6376d13a-f419-4461-a6be-6d15524b7ace" xlink:to="loc_srt_ScenarioUnspecifiedDomain_6376d13a-f419-4461-a6be-6d15524b7ace_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioUnspecifiedDomain_553f1c32-863f-4086-9b4f-9ecefdf95ee9" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ScenarioUnspecifiedDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementScenarioAxis_6376d13a-f419-4461-a6be-6d15524b7ace" xlink:to="loc_srt_ScenarioUnspecifiedDomain_553f1c32-863f-4086-9b4f-9ecefdf95ee9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioForecastMember_7c0c8c1b-a371-46c0-a888-2d855a6ca145" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ScenarioForecastMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ScenarioUnspecifiedDomain_553f1c32-863f-4086-9b4f-9ecefdf95ee9" xlink:to="loc_srt_ScenarioForecastMember_7c0c8c1b-a371-46c0-a888-2d855a6ca145" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_6de9150c-98c8-4e8c-85c9-95e8a5d7e045" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsequentEventTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_71f62344-17f2-42cb-81d3-bdb94309817a" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_6de9150c-98c8-4e8c-85c9-95e8a5d7e045" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_6de9150c-98c8-4e8c-85c9-95e8a5d7e045_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_6de9150c-98c8-4e8c-85c9-95e8a5d7e045" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_6de9150c-98c8-4e8c-85c9-95e8a5d7e045_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_94a65262-923b-4509-8c0a-6e4df0ea2b6a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_6de9150c-98c8-4e8c-85c9-95e8a5d7e045" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_94a65262-923b-4509-8c0a-6e4df0ea2b6a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventMember_24d747cd-db7f-41a4-b593-7e585acf1fcd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsequentEventMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_94a65262-923b-4509-8c0a-6e4df0ea2b6a" xlink:to="loc_us-gaap_SubsequentEventMember_24d747cd-db7f-41a4-b593-7e585acf1fcd" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_DateInitiatedAxis_bf910123-2304-4607-b9b7-e7383899e987" xlink:href="cah-20241231.xsd#cah_DateInitiatedAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_71f62344-17f2-42cb-81d3-bdb94309817a" xlink:to="loc_cah_DateInitiatedAxis_bf910123-2304-4607-b9b7-e7383899e987" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_DateInitiatedDomain_bf910123-2304-4607-b9b7-e7383899e987_default" xlink:href="cah-20241231.xsd#cah_DateInitiatedDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_cah_DateInitiatedAxis_bf910123-2304-4607-b9b7-e7383899e987" xlink:to="loc_cah_DateInitiatedDomain_bf910123-2304-4607-b9b7-e7383899e987_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_DateInitiatedDomain_719f60c0-519c-4ab9-ac58-7a1928c3f61b" xlink:href="cah-20241231.xsd#cah_DateInitiatedDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_cah_DateInitiatedAxis_bf910123-2304-4607-b9b7-e7383899e987" xlink:to="loc_cah_DateInitiatedDomain_719f60c0-519c-4ab9-ac58-7a1928c3f61b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_January2023Member_d2458679-dc60-444b-9821-223426a74547" xlink:href="cah-20241231.xsd#cah_January2023Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_cah_DateInitiatedDomain_719f60c0-519c-4ab9-ac58-7a1928c3f61b" xlink:to="loc_cah_January2023Member_d2458679-dc60-444b-9821-223426a74547" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_September2023Member_8299ccb9-d0a1-4ce5-97df-d30f38b24507" xlink:href="cah-20241231.xsd#cah_September2023Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_cah_DateInitiatedDomain_719f60c0-519c-4ab9-ac58-7a1928c3f61b" xlink:to="loc_cah_September2023Member_8299ccb9-d0a1-4ce5-97df-d30f38b24507" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ChangeInUnrealizedGainLossOnFairValueHedgingInstruments1_a7f1c05c-ff66-4805-b233-73b9c8dbaff4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ChangeInUnrealizedGainLossOnFairValueHedgingInstruments1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_6fa4cefe-c4c6-45ff-9106-cb80a00560f0" xlink:to="loc_us-gaap_ChangeInUnrealizedGainLossOnFairValueHedgingInstruments1_a7f1c05c-ff66-4805-b233-73b9c8dbaff4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilityNotionalAmount_44e770ce-2592-4bf8-9752-3e15d2052c1d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeLiabilityNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_6fa4cefe-c4c6-45ff-9106-cb80a00560f0" xlink:to="loc_us-gaap_DerivativeLiabilityNotionalAmount_44e770ce-2592-4bf8-9752-3e15d2052c1d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax_484638b6-37b8-4fdf-9bc9-e038c74f5e4b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_6fa4cefe-c4c6-45ff-9106-cb80a00560f0" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax_484638b6-37b8-4fdf-9bc9-e038c74f5e4b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet_efedf0ac-db84-4150-afd9-e26baecb372d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_6fa4cefe-c4c6-45ff-9106-cb80a00560f0" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet_efedf0ac-db84-4150-afd9-e26baecb372d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeNotionalAmount_53e86757-be3e-4f54-b070-0bdb44134ee6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_6fa4cefe-c4c6-45ff-9106-cb80a00560f0" xlink:to="loc_us-gaap_DerivativeNotionalAmount_53e86757-be3e-4f54-b070-0bdb44134ee6" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_DerivativesHedgeDiscontinuancesTerminationOfHedgingInstrumentNotionalAmount_d3b77d2d-95ef-4fd7-be6c-054472f7ff90" xlink:href="cah-20241231.xsd#cah_DerivativesHedgeDiscontinuancesTerminationOfHedgingInstrumentNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_6fa4cefe-c4c6-45ff-9106-cb80a00560f0" xlink:to="loc_cah_DerivativesHedgeDiscontinuancesTerminationOfHedgingInstrumentNotionalAmount_d3b77d2d-95ef-4fd7-be6c-054472f7ff90" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromHedgeInvestingActivities_81251fea-ef6f-409c-80cb-d1d31e5bc724" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProceedsFromHedgeInvestingActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_6fa4cefe-c4c6-45ff-9106-cb80a00560f0" xlink:to="loc_us-gaap_ProceedsFromHedgeInvestingActivities_81251fea-ef6f-409c-80cb-d1d31e5bc724" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetInvestmentHedgeGainLossBeforeReclassificationAndTax_29c7f3b4-15f5-4cbb-b49e-3602747f0f18" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherComprehensiveIncomeLossNetInvestmentHedgeGainLossBeforeReclassificationAndTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_6fa4cefe-c4c6-45ff-9106-cb80a00560f0" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetInvestmentHedgeGainLossBeforeReclassificationAndTax_29c7f3b4-15f5-4cbb-b49e-3602747f0f18" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsGainLossNet_1bd19848-f386-4e9e-8142-c0ad062cd8b5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsGainLossNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_6fa4cefe-c4c6-45ff-9106-cb80a00560f0" xlink:to="loc_us-gaap_DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsGainLossNet_1bd19848-f386-4e9e-8142-c0ad062cd8b5" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossRecognizedInIncomeIneffectivePortionAndAmountExcludedFromEffectivenessTestingNet_499e47f4-546f-4d0e-aa7c-776735acc118" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentsGainLossRecognizedInIncomeIneffectivePortionAndAmountExcludedFromEffectivenessTestingNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_6fa4cefe-c4c6-45ff-9106-cb80a00560f0" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossRecognizedInIncomeIneffectivePortionAndAmountExcludedFromEffectivenessTestingNet_499e47f4-546f-4d0e-aa7c-776735acc118" xlink:type="arc" order="9"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cardinal.com/role/FinancialInstrumentsSummaryofEstimatedFairValueofLongtermObligationsandOtherShorttermBorrowingsDetails" xlink:type="simple" xlink:href="cah-20241231.xsd#FinancialInstrumentsSummaryofEstimatedFairValueofLongtermObligationsandOtherShorttermBorrowingsDetails"/>
  <link:definitionLink xlink:role="http://www.cardinal.com/role/FinancialInstrumentsSummaryofEstimatedFairValueofLongtermObligationsandOtherShorttermBorrowingsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_bee03181-a176-4b11-8281-a8afa3f8ae40" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_0fe0d4a1-bce1-40db-ab39-62b7bd1cd4ca" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_bee03181-a176-4b11-8281-a8afa3f8ae40" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_0fe0d4a1-bce1-40db-ab39-62b7bd1cd4ca" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_bc3584ae-e1a9-45b5-a14e-cde4e4af955e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_0fe0d4a1-bce1-40db-ab39-62b7bd1cd4ca" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_bc3584ae-e1a9-45b5-a14e-cde4e4af955e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_bc3584ae-e1a9-45b5-a14e-cde4e4af955e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_bc3584ae-e1a9-45b5-a14e-cde4e4af955e" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_bc3584ae-e1a9-45b5-a14e-cde4e4af955e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_551a3a22-ed5a-4aea-b2b0-ebdda06849fc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_bc3584ae-e1a9-45b5-a14e-cde4e4af955e" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_551a3a22-ed5a-4aea-b2b0-ebdda06849fc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_402bb3a7-04ef-45c2-8f86-d05de22d3efb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueInputsLevel2Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_551a3a22-ed5a-4aea-b2b0-ebdda06849fc" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_402bb3a7-04ef-45c2-8f86-d05de22d3efb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentFairValue_b64a33e8-1c28-461f-b166-9032b8e8dcbf" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_bee03181-a176-4b11-8281-a8afa3f8ae40" xlink:to="loc_us-gaap_DebtInstrumentFairValue_b64a33e8-1c28-461f-b166-9032b8e8dcbf" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_CarryingAmountofLongTermandotherShortTermBorrowings_8c85fcfa-455d-4c10-992e-22948228a820" xlink:href="cah-20241231.xsd#cah_CarryingAmountofLongTermandotherShortTermBorrowings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_bee03181-a176-4b11-8281-a8afa3f8ae40" xlink:to="loc_cah_CarryingAmountofLongTermandotherShortTermBorrowings_8c85fcfa-455d-4c10-992e-22948228a820" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cardinal.com/role/ShareholdersEquityNarrativeDetails" xlink:type="simple" xlink:href="cah-20241231.xsd#ShareholdersEquityNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.cardinal.com/role/ShareholdersEquityNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockLineItems_f642ba75-24ff-40b1-bb94-f2e1816899c2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ClassOfStockLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfStockByClassTable_c803b252-22fc-44a9-b1a5-06885c4d5ccd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfStockByClassTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ClassOfStockLineItems_f642ba75-24ff-40b1-bb94-f2e1816899c2" xlink:to="loc_us-gaap_ScheduleOfStockByClassTable_c803b252-22fc-44a9-b1a5-06885c4d5ccd" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_cc59ee0a-97d5-47ec-b755-a5aafda03a52" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_c803b252-22fc-44a9-b1a5-06885c4d5ccd" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_cc59ee0a-97d5-47ec-b755-a5aafda03a52" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_cc59ee0a-97d5-47ec-b755-a5aafda03a52_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_cc59ee0a-97d5-47ec-b755-a5aafda03a52" xlink:to="loc_us-gaap_EquityComponentDomain_cc59ee0a-97d5-47ec-b755-a5aafda03a52_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_691816c9-1245-4a74-b1e4-c0642fd11c23" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_cc59ee0a-97d5-47ec-b755-a5aafda03a52" xlink:to="loc_us-gaap_EquityComponentDomain_691816c9-1245-4a74-b1e4-c0642fd11c23" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockCommonMember_b4edd30d-fd52-4153-a26a-3b942debb3aa" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TreasuryStockCommonMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_691816c9-1245-4a74-b1e4-c0642fd11c23" xlink:to="loc_us-gaap_TreasuryStockCommonMember_b4edd30d-fd52-4153-a26a-3b942debb3aa" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockCommonMember_7a932999-eb44-410b-a66a-a5204ee843e2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TreasuryStockCommonMember"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_93e5199f-d017-4eed-91e3-d1928ee2bbfa" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsequentEventTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_c803b252-22fc-44a9-b1a5-06885c4d5ccd" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_93e5199f-d017-4eed-91e3-d1928ee2bbfa" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_93e5199f-d017-4eed-91e3-d1928ee2bbfa_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_93e5199f-d017-4eed-91e3-d1928ee2bbfa" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_93e5199f-d017-4eed-91e3-d1928ee2bbfa_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_dec8cb6f-acbb-4442-982d-54b8de4a8365" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_93e5199f-d017-4eed-91e3-d1928ee2bbfa" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_dec8cb6f-acbb-4442-982d-54b8de4a8365" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventMember_bfa25b62-2003-4ac1-8306-66a2b282da6b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsequentEventMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_dec8cb6f-acbb-4442-982d-54b8de4a8365" xlink:to="loc_us-gaap_SubsequentEventMember_bfa25b62-2003-4ac1-8306-66a2b282da6b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramAxis_63d60ad4-d8fa-462a-acfd-d023effd2236" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ShareRepurchaseProgramAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_c803b252-22fc-44a9-b1a5-06885c4d5ccd" xlink:to="loc_srt_ShareRepurchaseProgramAxis_63d60ad4-d8fa-462a-acfd-d023effd2236" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramDomain_63d60ad4-d8fa-462a-acfd-d023effd2236_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ShareRepurchaseProgramDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ShareRepurchaseProgramAxis_63d60ad4-d8fa-462a-acfd-d023effd2236" xlink:to="loc_srt_ShareRepurchaseProgramDomain_63d60ad4-d8fa-462a-acfd-d023effd2236_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramDomain_e69c014e-ad5f-47ac-989d-e40d01562c3f" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ShareRepurchaseProgramDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ShareRepurchaseProgramAxis_63d60ad4-d8fa-462a-acfd-d023effd2236" xlink:to="loc_srt_ShareRepurchaseProgramDomain_e69c014e-ad5f-47ac-989d-e40d01562c3f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_A250MillionShareRepurchaseProgramMember_dbb8bb6b-63cd-4962-acfe-82e4ab1566cc" xlink:href="cah-20241231.xsd#cah_A250MillionShareRepurchaseProgramMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ShareRepurchaseProgramDomain_e69c014e-ad5f-47ac-989d-e40d01562c3f" xlink:to="loc_cah_A250MillionShareRepurchaseProgramMember_dbb8bb6b-63cd-4962-acfe-82e4ab1566cc" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_A500MillionShareRepurchaseProgramMember_0ae284bb-9d26-4b7f-ab04-0f8ced28b2e0" xlink:href="cah-20241231.xsd#cah_A500MillionShareRepurchaseProgramMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ShareRepurchaseProgramDomain_e69c014e-ad5f-47ac-989d-e40d01562c3f" xlink:to="loc_cah_A500MillionShareRepurchaseProgramMember_0ae284bb-9d26-4b7f-ab04-0f8ced28b2e0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_A375MillionShareRepurchaseProgramMember_6ce180dd-88aa-4fa0-9f6b-a8b54def7e20" xlink:href="cah-20241231.xsd#cah_A375MillionShareRepurchaseProgramMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ShareRepurchaseProgramDomain_e69c014e-ad5f-47ac-989d-e40d01562c3f" xlink:to="loc_cah_A375MillionShareRepurchaseProgramMember_6ce180dd-88aa-4fa0-9f6b-a8b54def7e20" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForRepurchaseOfCommonStock_3ed5025d-e6f7-45a9-95b9-eb9906ceb989" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PaymentsForRepurchaseOfCommonStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_f642ba75-24ff-40b1-bb94-f2e1816899c2" xlink:to="loc_us-gaap_PaymentsForRepurchaseOfCommonStock_3ed5025d-e6f7-45a9-95b9-eb9906ceb989" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockSharesAcquired_22e0e468-1a64-4865-9d74-e1a14a7ce730" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TreasuryStockSharesAcquired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_f642ba75-24ff-40b1-bb94-f2e1816899c2" xlink:to="loc_us-gaap_TreasuryStockSharesAcquired_22e0e468-1a64-4865-9d74-e1a14a7ce730" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockAcquiredAverageCostPerShare_59235acf-9ca2-4da3-b947-1dc854e6efaa" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TreasuryStockAcquiredAverageCostPerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_f642ba75-24ff-40b1-bb94-f2e1816899c2" xlink:to="loc_us-gaap_TreasuryStockAcquiredAverageCostPerShare_59235acf-9ca2-4da3-b947-1dc854e6efaa" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockSharesRetired_2a641c31-a284-4a45-a598-4c9c19c795f8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TreasuryStockSharesRetired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_f642ba75-24ff-40b1-bb94-f2e1816899c2" xlink:to="loc_us-gaap_TreasuryStockSharesRetired_2a641c31-a284-4a45-a598-4c9c19c795f8" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cardinal.com/role/ShareholdersEquityChangesintheAccumulatedOtherComprehensiveIncomeLossDetails" xlink:type="simple" xlink:href="cah-20241231.xsd#ShareholdersEquityChangesintheAccumulatedOtherComprehensiveIncomeLossDetails"/>
  <link:definitionLink xlink:role="http://www.cardinal.com/role/ShareholdersEquityChangesintheAccumulatedOtherComprehensiveIncomeLossDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems_eb720eec-84cc-48f6-8a1f-430217acda65" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable_fb912665-d9e1-4909-b77f-c09701d2d9c8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems_eb720eec-84cc-48f6-8a1f-430217acda65" xlink:to="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable_fb912665-d9e1-4909-b77f-c09701d2d9c8" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_79e0230c-b785-4aeb-9bab-e3b0c992055b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable_fb912665-d9e1-4909-b77f-c09701d2d9c8" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_79e0230c-b785-4aeb-9bab-e3b0c992055b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_79e0230c-b785-4aeb-9bab-e3b0c992055b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_79e0230c-b785-4aeb-9bab-e3b0c992055b" xlink:to="loc_us-gaap_EquityComponentDomain_79e0230c-b785-4aeb-9bab-e3b0c992055b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_17e5ce04-d866-4be4-9a56-dfcf90568c27" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_79e0230c-b785-4aeb-9bab-e3b0c992055b" xlink:to="loc_us-gaap_EquityComponentDomain_17e5ce04-d866-4be4-9a56-dfcf90568c27" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedForeignCurrencyAdjustmentIncludingPortionAttributableToNoncontrollingInterestMember_ac792f36-7c16-4b66-b8fd-d7bbbc45a1e2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccumulatedForeignCurrencyAdjustmentIncludingPortionAttributableToNoncontrollingInterestMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_17e5ce04-d866-4be4-9a56-dfcf90568c27" xlink:to="loc_us-gaap_AccumulatedForeignCurrencyAdjustmentIncludingPortionAttributableToNoncontrollingInterestMember_ac792f36-7c16-4b66-b8fd-d7bbbc45a1e2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedNetGainLossFromCashFlowHedgesIncludingPortionAttributableToNoncontrollingInterestMember_040291bf-0fd8-43c5-9863-ebe7550b7c2f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccumulatedNetGainLossFromCashFlowHedgesIncludingPortionAttributableToNoncontrollingInterestMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_17e5ce04-d866-4be4-9a56-dfcf90568c27" xlink:to="loc_us-gaap_AccumulatedNetGainLossFromCashFlowHedgesIncludingPortionAttributableToNoncontrollingInterestMember_040291bf-0fd8-43c5-9863-ebe7550b7c2f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AociIncludingPortionAttributableToNoncontrollingInterestMember_2f46785c-b36b-4948-8553-616b944ef5f7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AociIncludingPortionAttributableToNoncontrollingInterestMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_17e5ce04-d866-4be4-9a56-dfcf90568c27" xlink:to="loc_us-gaap_AociIncludingPortionAttributableToNoncontrollingInterestMember_2f46785c-b36b-4948-8553-616b944ef5f7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_b3623000-5fb4-4627-8b30-63b1cef87434" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_17e5ce04-d866-4be4-9a56-dfcf90568c27" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_b3623000-5fb4-4627-8b30-63b1cef87434" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTaxAbstract_db8186f2-c5d7-4f32-be8f-f34f957d15da" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTaxAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems_eb720eec-84cc-48f6-8a1f-430217acda65" xlink:to="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTaxAbstract_db8186f2-c5d7-4f32-be8f-f34f957d15da" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_2da30682-4cdf-4589-bac7-577907fa1b97" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTaxAbstract_db8186f2-c5d7-4f32-be8f-f34f957d15da" xlink:to="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_2da30682-4cdf-4589-bac7-577907fa1b97" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax_a7169ef9-be24-4cb8-8d35-e15543d3be39" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTaxAbstract_db8186f2-c5d7-4f32-be8f-f34f957d15da" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax_a7169ef9-be24-4cb8-8d35-e15543d3be39" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax_6219e63f-2299-4269-9eeb-ab2d8b56ae12" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTaxAbstract_db8186f2-c5d7-4f32-be8f-f34f957d15da" xlink:to="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax_6219e63f-2299-4269-9eeb-ab2d8b56ae12" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossTax_3e941bf8-e0b8-49d9-a3ad-d9710a26bfdb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherComprehensiveIncomeLossTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTaxAbstract_db8186f2-c5d7-4f32-be8f-f34f957d15da" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossTax_3e941bf8-e0b8-49d9-a3ad-d9710a26bfdb" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_4c58e9ad-ba43-4a0b-b8da-05d0ed24a491" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTaxAbstract_db8186f2-c5d7-4f32-be8f-f34f957d15da" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_4c58e9ad-ba43-4a0b-b8da-05d0ed24a491" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_4dfacce5-8400-4fda-b1df-49f3dd0b04af" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cardinal.com/role/SegmentInformationNarrativeDetails" xlink:type="simple" xlink:href="cah-20241231.xsd#SegmentInformationNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.cardinal.com/role/SegmentInformationNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_7b28f88e-02af-4677-a38d-105cfbf9e68c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentReportingInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_b53c1f74-4c45-4064-96fe-b3c03dad740d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_7b28f88e-02af-4677-a38d-105cfbf9e68c" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_b53c1f74-4c45-4064-96fe-b3c03dad740d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_42eea942-515f-4fa9-baaf-baee0b8782d6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_b53c1f74-4c45-4064-96fe-b3c03dad740d" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_42eea942-515f-4fa9-baaf-baee0b8782d6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_42eea942-515f-4fa9-baaf-baee0b8782d6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_42eea942-515f-4fa9-baaf-baee0b8782d6" xlink:to="loc_us-gaap_SegmentDomain_42eea942-515f-4fa9-baaf-baee0b8782d6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_11ceb1f2-618e-4874-b448-4d4e4bc5597c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_42eea942-515f-4fa9-baaf-baee0b8782d6" xlink:to="loc_us-gaap_SegmentDomain_11ceb1f2-618e-4874-b448-4d4e4bc5597c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_GMPDMember_892d372b-784d-432f-8a57-24bf520be101" xlink:href="cah-20241231.xsd#cah_GMPDMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_11ceb1f2-618e-4874-b448-4d4e4bc5597c" xlink:to="loc_cah_GMPDMember_892d372b-784d-432f-8a57-24bf520be101" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllOtherSegmentsMember_da7992ed-afac-4700-8142-dbb583282961" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AllOtherSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_11ceb1f2-618e-4874-b448-4d4e4bc5597c" xlink:to="loc_us-gaap_AllOtherSegmentsMember_da7992ed-afac-4700-8142-dbb583282961" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReportingUnitAxis_7435b885-3740-4c0a-a209-361dd0dddec2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ReportingUnitAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_b53c1f74-4c45-4064-96fe-b3c03dad740d" xlink:to="loc_us-gaap_ReportingUnitAxis_7435b885-3740-4c0a-a209-361dd0dddec2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReportingUnitDomain_7435b885-3740-4c0a-a209-361dd0dddec2_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ReportingUnitDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ReportingUnitAxis_7435b885-3740-4c0a-a209-361dd0dddec2" xlink:to="loc_us-gaap_ReportingUnitDomain_7435b885-3740-4c0a-a209-361dd0dddec2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReportingUnitDomain_2a5b7cff-3ecd-4c50-b0a1-9d11c578ddc7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ReportingUnitDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ReportingUnitAxis_7435b885-3740-4c0a-a209-361dd0dddec2" xlink:to="loc_us-gaap_ReportingUnitDomain_2a5b7cff-3ecd-4c50-b0a1-9d11c578ddc7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_OptiFreightLogisticsMember_e10a4b57-66f5-4254-a56f-0aae4ae573f9" xlink:href="cah-20241231.xsd#cah_OptiFreightLogisticsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReportingUnitDomain_2a5b7cff-3ecd-4c50-b0a1-9d11c578ddc7" xlink:to="loc_cah_OptiFreightLogisticsMember_e10a4b57-66f5-4254-a56f-0aae4ae573f9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_AtHomeSolutionsMember_208c16e7-ec89-42f9-b0a6-b634416d2d50" xlink:href="cah-20241231.xsd#cah_AtHomeSolutionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReportingUnitDomain_2a5b7cff-3ecd-4c50-b0a1-9d11c578ddc7" xlink:to="loc_cah_AtHomeSolutionsMember_208c16e7-ec89-42f9-b0a6-b634416d2d50" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfReportableSegments_3d5cd4e9-c21e-428b-a869-46e6efbbe110" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NumberOfReportableSegments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_7b28f88e-02af-4677-a38d-105cfbf9e68c" xlink:to="loc_us-gaap_NumberOfReportableSegments_3d5cd4e9-c21e-428b-a869-46e6efbbe110" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfOperatingSegments_0f67d666-3fe9-4ce8-8fe8-99e7af595102" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NumberOfOperatingSegments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_7b28f88e-02af-4677-a38d-105cfbf9e68c" xlink:to="loc_us-gaap_NumberOfOperatingSegments_0f67d666-3fe9-4ce8-8fe8-99e7af595102" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillImpairmentLoss_b0abdb02-69c3-4a4a-beb8-4f9c36fa3210" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GoodwillImpairmentLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_7b28f88e-02af-4677-a38d-105cfbf9e68c" xlink:to="loc_us-gaap_GoodwillImpairmentLoss_b0abdb02-69c3-4a4a-beb8-4f9c36fa3210" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_ProjectCostsOnInvestmentAndOtherSpending_d6c4f7fb-273b-4cc6-8bb5-4ecbca522683" xlink:href="cah-20241231.xsd#cah_ProjectCostsOnInvestmentAndOtherSpending"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_7b28f88e-02af-4677-a38d-105cfbf9e68c" xlink:to="loc_cah_ProjectCostsOnInvestmentAndOtherSpending_d6c4f7fb-273b-4cc6-8bb5-4ecbca522683" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cardinal.com/role/SegmentInformationRevenuebyReportableSegmentDetails" xlink:type="simple" xlink:href="cah-20241231.xsd#SegmentInformationRevenuebyReportableSegmentDetails"/>
  <link:definitionLink xlink:role="http://www.cardinal.com/role/SegmentInformationRevenuebyReportableSegmentDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_168142f0-5eee-4b84-aa44-9406d11a2f0c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentReportingInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable_9dc11419-abf0-47fc-9a5d-8de6661a2a88" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_168142f0-5eee-4b84-aa44-9406d11a2f0c" xlink:to="loc_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable_9dc11419-abf0-47fc-9a5d-8de6661a2a88" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsegmentsAxis_4b70c50c-b19f-45db-8099-23f55c171410" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable_9dc11419-abf0-47fc-9a5d-8de6661a2a88" xlink:to="loc_us-gaap_SubsegmentsAxis_4b70c50c-b19f-45db-8099-23f55c171410" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsegmentsDomain_4b70c50c-b19f-45db-8099-23f55c171410_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsegmentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsegmentsAxis_4b70c50c-b19f-45db-8099-23f55c171410" xlink:to="loc_us-gaap_SubsegmentsDomain_4b70c50c-b19f-45db-8099-23f55c171410_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsegmentsDomain_0ad9b15f-b97e-4f7d-8707-99a9bbcae9ee" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SubsegmentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsegmentsAxis_4b70c50c-b19f-45db-8099-23f55c171410" xlink:to="loc_us-gaap_SubsegmentsDomain_0ad9b15f-b97e-4f7d-8707-99a9bbcae9ee" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_NuclearPrecisionHealthSolutionsMember_ab9e1c4a-ff81-47ec-a256-9e74ed03c8a0" xlink:href="cah-20241231.xsd#cah_NuclearPrecisionHealthSolutionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsegmentsDomain_0ad9b15f-b97e-4f7d-8707-99a9bbcae9ee" xlink:to="loc_cah_NuclearPrecisionHealthSolutionsMember_ab9e1c4a-ff81-47ec-a256-9e74ed03c8a0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_OptiFreightLogisticsMember_2701715c-68df-4bab-b7c5-ab01e7457a38" xlink:href="cah-20241231.xsd#cah_OptiFreightLogisticsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsegmentsDomain_0ad9b15f-b97e-4f7d-8707-99a9bbcae9ee" xlink:to="loc_cah_OptiFreightLogisticsMember_2701715c-68df-4bab-b7c5-ab01e7457a38" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_AtHomeSolutionsMember_3290ae6a-d7b4-44ec-8660-bed4993de0a9" xlink:href="cah-20241231.xsd#cah_AtHomeSolutionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsegmentsDomain_0ad9b15f-b97e-4f7d-8707-99a9bbcae9ee" xlink:to="loc_cah_AtHomeSolutionsMember_3290ae6a-d7b4-44ec-8660-bed4993de0a9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsAxis_046fbc40-a6c1-4f49-b89c-2becd02c16ed" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ConsolidationItemsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable_9dc11419-abf0-47fc-9a5d-8de6661a2a88" xlink:to="loc_srt_ConsolidationItemsAxis_046fbc40-a6c1-4f49-b89c-2becd02c16ed" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_046fbc40-a6c1-4f49-b89c-2becd02c16ed_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_046fbc40-a6c1-4f49-b89c-2becd02c16ed" xlink:to="loc_srt_ConsolidationItemsDomain_046fbc40-a6c1-4f49-b89c-2becd02c16ed_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_ad2f62a2-ec22-4147-97bb-811057fc3b59" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_046fbc40-a6c1-4f49-b89c-2becd02c16ed" xlink:to="loc_srt_ConsolidationItemsDomain_ad2f62a2-ec22-4147-97bb-811057fc3b59" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingSegmentsMember_049f6c74-86fb-4d2d-b0d6-35efc45fee76" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OperatingSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_ad2f62a2-ec22-4147-97bb-811057fc3b59" xlink:to="loc_us-gaap_OperatingSegmentsMember_049f6c74-86fb-4d2d-b0d6-35efc45fee76" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateNonSegmentMember_43aa015a-738d-425e-912d-e7815885b88a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CorporateNonSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_ad2f62a2-ec22-4147-97bb-811057fc3b59" xlink:to="loc_us-gaap_CorporateNonSegmentMember_43aa015a-738d-425e-912d-e7815885b88a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_bf0fe431-d4e9-4dc5-9738-d7d02fccbee6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable_9dc11419-abf0-47fc-9a5d-8de6661a2a88" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_bf0fe431-d4e9-4dc5-9738-d7d02fccbee6" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_bf0fe431-d4e9-4dc5-9738-d7d02fccbee6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_bf0fe431-d4e9-4dc5-9738-d7d02fccbee6" xlink:to="loc_us-gaap_SegmentDomain_bf0fe431-d4e9-4dc5-9738-d7d02fccbee6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_4efed90f-b776-4136-a385-2696db39a791" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_bf0fe431-d4e9-4dc5-9738-d7d02fccbee6" xlink:to="loc_us-gaap_SegmentDomain_4efed90f-b776-4136-a385-2696db39a791" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_PharmaceuticalAndSpecialtySolutionsMember_b5d22630-69d6-4878-8a7b-4dda7c1f876e" xlink:href="cah-20241231.xsd#cah_PharmaceuticalAndSpecialtySolutionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_4efed90f-b776-4136-a385-2696db39a791" xlink:to="loc_cah_PharmaceuticalAndSpecialtySolutionsMember_b5d22630-69d6-4878-8a7b-4dda7c1f876e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_GMPDMember_629dd6f5-7997-4960-97f8-02a20f2a6f1b" xlink:href="cah-20241231.xsd#cah_GMPDMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_4efed90f-b776-4136-a385-2696db39a791" xlink:to="loc_cah_GMPDMember_629dd6f5-7997-4960-97f8-02a20f2a6f1b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllOtherSegmentsMember_2a7d21ed-ac97-4d6b-b629-4032c82f13e5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AllOtherSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_4efed90f-b776-4136-a385-2696db39a791" xlink:to="loc_us-gaap_AllOtherSegmentsMember_2a7d21ed-ac97-4d6b-b629-4032c82f13e5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Revenues_b92c236f-5d35-46e0-b7e9-ae078c2229f0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Revenues"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_168142f0-5eee-4b84-aa44-9406d11a2f0c" xlink:to="loc_us-gaap_Revenues_b92c236f-5d35-46e0-b7e9-ae078c2229f0" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cardinal.com/role/SegmentInformationRevenueFromExternalCustomersByGeographicAreasDetails" xlink:type="simple" xlink:href="cah-20241231.xsd#SegmentInformationRevenueFromExternalCustomersByGeographicAreasDetails"/>
  <link:definitionLink xlink:role="http://www.cardinal.com/role/SegmentInformationRevenueFromExternalCustomersByGeographicAreasDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_cah_SegmentRevenuefromExternalCustomersbyGeographicAreaLineItems_a080f9fc-8b71-4d7e-aad0-a684fba821b6" xlink:href="cah-20241231.xsd#cah_SegmentRevenuefromExternalCustomersbyGeographicAreaLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_SegmentRevenuefromExternalCustomersbyGeographicAreaTable_cf5194b5-26c2-4f70-97f4-96f5819de37d" xlink:href="cah-20241231.xsd#cah_SegmentRevenuefromExternalCustomersbyGeographicAreaTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_cah_SegmentRevenuefromExternalCustomersbyGeographicAreaLineItems_a080f9fc-8b71-4d7e-aad0-a684fba821b6" xlink:to="loc_cah_SegmentRevenuefromExternalCustomersbyGeographicAreaTable_cf5194b5-26c2-4f70-97f4-96f5819de37d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsAxis_a9cb724e-d6e6-4012-a5d6-55505fe40760" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ConsolidationItemsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_cah_SegmentRevenuefromExternalCustomersbyGeographicAreaTable_cf5194b5-26c2-4f70-97f4-96f5819de37d" xlink:to="loc_srt_ConsolidationItemsAxis_a9cb724e-d6e6-4012-a5d6-55505fe40760" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_a9cb724e-d6e6-4012-a5d6-55505fe40760_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_a9cb724e-d6e6-4012-a5d6-55505fe40760" xlink:to="loc_srt_ConsolidationItemsDomain_a9cb724e-d6e6-4012-a5d6-55505fe40760_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_367f28c8-2d14-4034-b107-8881b8a2c5a3" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_a9cb724e-d6e6-4012-a5d6-55505fe40760" xlink:to="loc_srt_ConsolidationItemsDomain_367f28c8-2d14-4034-b107-8881b8a2c5a3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingSegmentsMember_9f032de1-a500-4cdb-9455-d734607a064e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OperatingSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_367f28c8-2d14-4034-b107-8881b8a2c5a3" xlink:to="loc_us-gaap_OperatingSegmentsMember_9f032de1-a500-4cdb-9455-d734607a064e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateNonSegmentMember_eb839ffe-4338-4b91-8765-a7a69ccfb2d8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CorporateNonSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_367f28c8-2d14-4034-b107-8881b8a2c5a3" xlink:to="loc_us-gaap_CorporateNonSegmentMember_eb839ffe-4338-4b91-8765-a7a69ccfb2d8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_daad2555-555e-440d-89de-a62adfd8f121" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_cah_SegmentRevenuefromExternalCustomersbyGeographicAreaTable_cf5194b5-26c2-4f70-97f4-96f5819de37d" xlink:to="loc_srt_StatementGeographicalAxis_daad2555-555e-440d-89de-a62adfd8f121" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_daad2555-555e-440d-89de-a62adfd8f121_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_daad2555-555e-440d-89de-a62adfd8f121" xlink:to="loc_srt_SegmentGeographicalDomain_daad2555-555e-440d-89de-a62adfd8f121_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_a211c4f8-00a0-4381-ac7e-ff5089024552" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_daad2555-555e-440d-89de-a62adfd8f121" xlink:to="loc_srt_SegmentGeographicalDomain_a211c4f8-00a0-4381-ac7e-ff5089024552" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_US_0393edd9-0c6b-4cf5-98d5-d2fdd304923c" xlink:href="https://xbrl.sec.gov/country/2024/country-2024.xsd#country_US"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_a211c4f8-00a0-4381-ac7e-ff5089024552" xlink:to="loc_country_US_0393edd9-0c6b-4cf5-98d5-d2fdd304923c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NonUsMember_6da8b8d7-f480-4aeb-a37e-a072470205f5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NonUsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_a211c4f8-00a0-4381-ac7e-ff5089024552" xlink:to="loc_us-gaap_NonUsMember_6da8b8d7-f480-4aeb-a37e-a072470205f5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Revenues_64c9049e-d5ae-4b1b-85d4-cdc585132ec9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Revenues"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_cah_SegmentRevenuefromExternalCustomersbyGeographicAreaLineItems_a080f9fc-8b71-4d7e-aad0-a684fba821b6" xlink:to="loc_us-gaap_Revenues_64c9049e-d5ae-4b1b-85d4-cdc585132ec9" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cardinal.com/role/SegmentInformationSegmentProfitbyReportableSegmentDetails" xlink:type="simple" xlink:href="cah-20241231.xsd#SegmentInformationSegmentProfitbyReportableSegmentDetails"/>
  <link:definitionLink xlink:role="http://www.cardinal.com/role/SegmentInformationSegmentProfitbyReportableSegmentDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingReconcilingItemForOperatingProfitLossFromSegmentToConsolidatedLineItems_5eae4ee3-d1fd-456d-b3a1-b675a54905e6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentReportingReconcilingItemForOperatingProfitLossFromSegmentToConsolidatedLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTable_a5a3fb54-5972-4ebb-9a71-470e24afe692" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingReconcilingItemForOperatingProfitLossFromSegmentToConsolidatedLineItems_5eae4ee3-d1fd-456d-b3a1-b675a54905e6" xlink:to="loc_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTable_a5a3fb54-5972-4ebb-9a71-470e24afe692" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_04396947-b19e-4eff-b95c-cb2d95dd0be6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTable_a5a3fb54-5972-4ebb-9a71-470e24afe692" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_04396947-b19e-4eff-b95c-cb2d95dd0be6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_04396947-b19e-4eff-b95c-cb2d95dd0be6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_04396947-b19e-4eff-b95c-cb2d95dd0be6" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_04396947-b19e-4eff-b95c-cb2d95dd0be6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_ee88900c-cad1-4465-9a6d-3a5105411336" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_04396947-b19e-4eff-b95c-cb2d95dd0be6" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_ee88900c-cad1-4465-9a6d-3a5105411336" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsAxis_4f3783c1-a857-436e-8841-ccbe93af2bba" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ConsolidationItemsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTable_a5a3fb54-5972-4ebb-9a71-470e24afe692" xlink:to="loc_srt_ConsolidationItemsAxis_4f3783c1-a857-436e-8841-ccbe93af2bba" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_4f3783c1-a857-436e-8841-ccbe93af2bba_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_4f3783c1-a857-436e-8841-ccbe93af2bba" xlink:to="loc_srt_ConsolidationItemsDomain_4f3783c1-a857-436e-8841-ccbe93af2bba_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_e6d03871-cb2c-4765-94f6-8f31e5cc70d0" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_4f3783c1-a857-436e-8841-ccbe93af2bba" xlink:to="loc_srt_ConsolidationItemsDomain_e6d03871-cb2c-4765-94f6-8f31e5cc70d0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingSegmentsMember_b5dacc88-f610-4ce7-a2a3-73dd3649ebfe" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OperatingSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_e6d03871-cb2c-4765-94f6-8f31e5cc70d0" xlink:to="loc_us-gaap_OperatingSegmentsMember_b5dacc88-f610-4ce7-a2a3-73dd3649ebfe" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateNonSegmentMember_75a27900-0ec4-4fb3-99d1-f2dab911ac6c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CorporateNonSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_e6d03871-cb2c-4765-94f6-8f31e5cc70d0" xlink:to="loc_us-gaap_CorporateNonSegmentMember_75a27900-0ec4-4fb3-99d1-f2dab911ac6c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_eb5018a8-d33a-446c-966a-ec2926e09963" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTable_a5a3fb54-5972-4ebb-9a71-470e24afe692" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_eb5018a8-d33a-446c-966a-ec2926e09963" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_eb5018a8-d33a-446c-966a-ec2926e09963_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_eb5018a8-d33a-446c-966a-ec2926e09963" xlink:to="loc_us-gaap_SegmentDomain_eb5018a8-d33a-446c-966a-ec2926e09963_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_ecc71300-850e-4668-8c12-5f082e62d0db" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_eb5018a8-d33a-446c-966a-ec2926e09963" xlink:to="loc_us-gaap_SegmentDomain_ecc71300-850e-4668-8c12-5f082e62d0db" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_PharmaceuticalAndSpecialtySolutionsMember_42ec52c3-1c8f-43b9-b5fa-c8cbc95dc19f" xlink:href="cah-20241231.xsd#cah_PharmaceuticalAndSpecialtySolutionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_ecc71300-850e-4668-8c12-5f082e62d0db" xlink:to="loc_cah_PharmaceuticalAndSpecialtySolutionsMember_42ec52c3-1c8f-43b9-b5fa-c8cbc95dc19f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_GMPDMember_4eeffab5-5533-41da-b00b-2bc78bb866eb" xlink:href="cah-20241231.xsd#cah_GMPDMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_ecc71300-850e-4668-8c12-5f082e62d0db" xlink:to="loc_cah_GMPDMember_4eeffab5-5533-41da-b00b-2bc78bb866eb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllOtherSegmentsMember_666669b0-5b47-433f-8474-a58d363d472c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AllOtherSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_ecc71300-850e-4668-8c12-5f082e62d0db" xlink:to="loc_us-gaap_AllOtherSegmentsMember_666669b0-5b47-433f-8474-a58d363d472c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingIncomeLoss_60c34762-af23-4578-b840-c30754140e47" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OperatingIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingReconcilingItemForOperatingProfitLossFromSegmentToConsolidatedLineItems_5eae4ee3-d1fd-456d-b3a1-b675a54905e6" xlink:to="loc_us-gaap_OperatingIncomeLoss_60c34762-af23-4578-b840-c30754140e47" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cardinal.com/role/SegmentInformationAssetsbyReportableSegmentDetails" xlink:type="simple" xlink:href="cah-20241231.xsd#SegmentInformationAssetsbyReportableSegmentDetails"/>
  <link:definitionLink xlink:role="http://www.cardinal.com/role/SegmentInformationAssetsbyReportableSegmentDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_0673fdd0-f3f4-4649-b526-3ae3c646759c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentReportingInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_fb953660-9d3a-4d1a-9300-21e2d1c1e155" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_0673fdd0-f3f4-4649-b526-3ae3c646759c" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_fb953660-9d3a-4d1a-9300-21e2d1c1e155" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsAxis_79ad2620-ad87-47a7-a524-ad6684af784c" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ConsolidationItemsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_fb953660-9d3a-4d1a-9300-21e2d1c1e155" xlink:to="loc_srt_ConsolidationItemsAxis_79ad2620-ad87-47a7-a524-ad6684af784c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_79ad2620-ad87-47a7-a524-ad6684af784c_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_79ad2620-ad87-47a7-a524-ad6684af784c" xlink:to="loc_srt_ConsolidationItemsDomain_79ad2620-ad87-47a7-a524-ad6684af784c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_79905a24-e170-401e-a581-b49607e95f56" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_79ad2620-ad87-47a7-a524-ad6684af784c" xlink:to="loc_srt_ConsolidationItemsDomain_79905a24-e170-401e-a581-b49607e95f56" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingSegmentsMember_4c351f44-a256-4068-a51c-6d4743d7f41f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OperatingSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_79905a24-e170-401e-a581-b49607e95f56" xlink:to="loc_us-gaap_OperatingSegmentsMember_4c351f44-a256-4068-a51c-6d4743d7f41f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateNonSegmentMember_3656f2b6-2b5e-4846-a150-f8c817850efa" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CorporateNonSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_79905a24-e170-401e-a581-b49607e95f56" xlink:to="loc_us-gaap_CorporateNonSegmentMember_3656f2b6-2b5e-4846-a150-f8c817850efa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_032c9a83-efe5-4082-b4da-60ea3257a5e7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_fb953660-9d3a-4d1a-9300-21e2d1c1e155" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_032c9a83-efe5-4082-b4da-60ea3257a5e7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_032c9a83-efe5-4082-b4da-60ea3257a5e7_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_032c9a83-efe5-4082-b4da-60ea3257a5e7" xlink:to="loc_us-gaap_SegmentDomain_032c9a83-efe5-4082-b4da-60ea3257a5e7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_36c26c9e-810d-4417-a7ad-24a51ef10ef2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_032c9a83-efe5-4082-b4da-60ea3257a5e7" xlink:to="loc_us-gaap_SegmentDomain_36c26c9e-810d-4417-a7ad-24a51ef10ef2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_PharmaceuticalAndSpecialtySolutionsMember_25bcd931-2501-4808-a070-382a3b14f5f7" xlink:href="cah-20241231.xsd#cah_PharmaceuticalAndSpecialtySolutionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_36c26c9e-810d-4417-a7ad-24a51ef10ef2" xlink:to="loc_cah_PharmaceuticalAndSpecialtySolutionsMember_25bcd931-2501-4808-a070-382a3b14f5f7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_GMPDMember_da22c756-2f2f-4a80-ab96-1b293e726576" xlink:href="cah-20241231.xsd#cah_GMPDMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_36c26c9e-810d-4417-a7ad-24a51ef10ef2" xlink:to="loc_cah_GMPDMember_da22c756-2f2f-4a80-ab96-1b293e726576" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllOtherSegmentsMember_b715568a-c68c-4c98-adb9-f3b90386dd2a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AllOtherSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_36c26c9e-810d-4417-a7ad-24a51ef10ef2" xlink:to="loc_us-gaap_AllOtherSegmentsMember_b715568a-c68c-4c98-adb9-f3b90386dd2a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_33b48c38-c505-4f12-a4af-ea427b8b6e21" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Assets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_0673fdd0-f3f4-4649-b526-3ae3c646759c" xlink:to="loc_us-gaap_Assets_33b48c38-c505-4f12-a4af-ea427b8b6e21" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cardinal.com/role/ShareBasedCompensationNarrativeDetails" xlink:type="simple" xlink:href="cah-20241231.xsd#ShareBasedCompensationNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.cardinal.com/role/ShareBasedCompensationNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_cfc463a0-1761-4e44-9270-6d1541ebf1ed" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_3cb7349a-6323-4f85-a460-52590d149a66" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_cfc463a0-1761-4e44-9270-6d1541ebf1ed" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_3cb7349a-6323-4f85-a460-52590d149a66" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_a9b656ee-6b16-4d34-84db-af6ac6ec1460" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_3cb7349a-6323-4f85-a460-52590d149a66" xlink:to="loc_us-gaap_AwardTypeAxis_a9b656ee-6b16-4d34-84db-af6ac6ec1460" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_a9b656ee-6b16-4d34-84db-af6ac6ec1460_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_a9b656ee-6b16-4d34-84db-af6ac6ec1460" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_a9b656ee-6b16-4d34-84db-af6ac6ec1460_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_cbf0951e-2adc-4ce3-a738-246ddc40b4ec" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_a9b656ee-6b16-4d34-84db-af6ac6ec1460" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_cbf0951e-2adc-4ce3-a738-246ddc40b4ec" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_5729be38-2781-42f4-a43b-7f4adbc91148" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_cbf0951e-2adc-4ce3-a738-246ddc40b4ec" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_5729be38-2781-42f4-a43b-7f4adbc91148" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PerformanceSharesMember_f8a83d31-a28d-4a83-a22b-6d738db1178b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PerformanceSharesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_cbf0951e-2adc-4ce3-a738-246ddc40b4ec" xlink:to="loc_us-gaap_PerformanceSharesMember_f8a83d31-a28d-4a83-a22b-6d738db1178b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_c14cfa09-4ab8-4358-93e4-7d6bd1be080c" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_3cb7349a-6323-4f85-a460-52590d149a66" xlink:to="loc_srt_RangeAxis_c14cfa09-4ab8-4358-93e4-7d6bd1be080c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_c14cfa09-4ab8-4358-93e4-7d6bd1be080c_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_c14cfa09-4ab8-4358-93e4-7d6bd1be080c" xlink:to="loc_srt_RangeMember_c14cfa09-4ab8-4358-93e4-7d6bd1be080c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_d5494391-146b-4e1b-b2a3-2a539b0d089b" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_c14cfa09-4ab8-4358-93e4-7d6bd1be080c" xlink:to="loc_srt_RangeMember_d5494391-146b-4e1b-b2a3-2a539b0d089b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_d810332b-683d-4da2-8107-1d22f63a78d2" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_d5494391-146b-4e1b-b2a3-2a539b0d089b" xlink:to="loc_srt_MinimumMember_d810332b-683d-4da2-8107-1d22f63a78d2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_3abd0d1f-9d36-4649-aa8e-b7294ae43c86" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_d5494391-146b-4e1b-b2a3-2a539b0d089b" xlink:to="loc_srt_MaximumMember_3abd0d1f-9d36-4649-aa8e-b7294ae43c86" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense_c8151143-ab96-42e7-bdb8-d74a7b10ecb6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_cfc463a0-1761-4e44-9270-6d1541ebf1ed" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense_c8151143-ab96-42e7-bdb8-d74a7b10ecb6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_15a47f29-99b9-45b6-8457-5fd7f33e488d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_cfc463a0-1761-4e44-9270-6d1541ebf1ed" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_15a47f29-99b9-45b6-8457-5fd7f33e488d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_fb2d63f6-667f-4d47-842c-27e0760996a3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_cfc463a0-1761-4e44-9270-6d1541ebf1ed" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_fb2d63f6-667f-4d47-842c-27e0760996a3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_0b17a9c7-5486-4e0d-8a2e-f4cce041180e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_cfc463a0-1761-4e44-9270-6d1541ebf1ed" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_0b17a9c7-5486-4e0d-8a2e-f4cce041180e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_cah_VestingPeriodinyearsforShares_dd4e2d9e-59e5-4ea7-a049-2654f82d3f9b" xlink:href="cah-20241231.xsd#cah_VestingPeriodinyearsforShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_cfc463a0-1761-4e44-9270-6d1541ebf1ed" xlink:to="loc_cah_VestingPeriodinyearsforShares_dd4e2d9e-59e5-4ea7-a049-2654f82d3f9b" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage_21dcbd3f-6e8b-4492-931c-6704fb8cc6b8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_cfc463a0-1761-4e44-9270-6d1541ebf1ed" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage_21dcbd3f-6e8b-4492-931c-6704fb8cc6b8" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cardinal.com/role/ShareBasedCompensationScheduleofTotalShareBasedCompensationExpensebyTypeofAwardDetails" xlink:type="simple" xlink:href="cah-20241231.xsd#ShareBasedCompensationScheduleofTotalShareBasedCompensationExpensebyTypeofAwardDetails"/>
  <link:definitionLink xlink:role="http://www.cardinal.com/role/ShareBasedCompensationScheduleofTotalShareBasedCompensationExpensebyTypeofAwardDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_50069668-450e-4dc5-9ff4-fb8a84007b03" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_33467111-763a-4b48-9c2f-9c3e109390da" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_50069668-450e-4dc5-9ff4-fb8a84007b03" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_33467111-763a-4b48-9c2f-9c3e109390da" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_8fb93b45-f0b6-4289-9f21-1f4be9795a9a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_33467111-763a-4b48-9c2f-9c3e109390da" xlink:to="loc_us-gaap_AwardTypeAxis_8fb93b45-f0b6-4289-9f21-1f4be9795a9a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_8fb93b45-f0b6-4289-9f21-1f4be9795a9a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_8fb93b45-f0b6-4289-9f21-1f4be9795a9a" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_8fb93b45-f0b6-4289-9f21-1f4be9795a9a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_0d17ef86-55b5-428d-9b7c-fd57f4dad712" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_8fb93b45-f0b6-4289-9f21-1f4be9795a9a" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_0d17ef86-55b5-428d-9b7c-fd57f4dad712" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_619bf478-2acb-4fc7-affb-4e8b91736d86" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_0d17ef86-55b5-428d-9b7c-fd57f4dad712" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_619bf478-2acb-4fc7-affb-4e8b91736d86" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PerformanceSharesMember_7a305ee7-2311-49bd-ab9d-27396097b306" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PerformanceSharesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_0d17ef86-55b5-428d-9b7c-fd57f4dad712" xlink:to="loc_us-gaap_PerformanceSharesMember_7a305ee7-2311-49bd-ab9d-27396097b306" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense_b8e6a799-0914-4d05-a8e7-e32b74d50394" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AllocatedShareBasedCompensationExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_50069668-450e-4dc5-9ff4-fb8a84007b03" xlink:to="loc_us-gaap_AllocatedShareBasedCompensationExpense_b8e6a799-0914-4d05-a8e7-e32b74d50394" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cardinal.com/role/ShareBasedCompensationScheduleofAllTransactionsRelatedtoRestrictedShareUnitsUnderthePlansDetails" xlink:type="simple" xlink:href="cah-20241231.xsd#ShareBasedCompensationScheduleofAllTransactionsRelatedtoRestrictedShareUnitsUnderthePlansDetails"/>
  <link:definitionLink xlink:role="http://www.cardinal.com/role/ShareBasedCompensationScheduleofAllTransactionsRelatedtoRestrictedShareUnitsUnderthePlansDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7a6d8a8c-e290-4206-a49b-9b9d3959a035" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_d2fac28f-7c4f-4756-898a-129a02bcb378" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7a6d8a8c-e290-4206-a49b-9b9d3959a035" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_d2fac28f-7c4f-4756-898a-129a02bcb378" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_9e871068-6704-46e3-a4fa-16f9ecfe3b8b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_d2fac28f-7c4f-4756-898a-129a02bcb378" xlink:to="loc_us-gaap_AwardTypeAxis_9e871068-6704-46e3-a4fa-16f9ecfe3b8b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_9e871068-6704-46e3-a4fa-16f9ecfe3b8b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_9e871068-6704-46e3-a4fa-16f9ecfe3b8b" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_9e871068-6704-46e3-a4fa-16f9ecfe3b8b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_d5b7893e-9ee6-4e2d-8be4-63441c6cd39b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_9e871068-6704-46e3-a4fa-16f9ecfe3b8b" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_d5b7893e-9ee6-4e2d-8be4-63441c6cd39b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_ea92a187-aa16-4c48-93e5-d7e7cbef2272" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_d5b7893e-9ee6-4e2d-8be4-63441c6cd39b" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_ea92a187-aa16-4c48-93e5-d7e7cbef2272" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_545fb870-995a-484b-8456-9b8180f8bb14" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7a6d8a8c-e290-4206-a49b-9b9d3959a035" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_545fb870-995a-484b-8456-9b8180f8bb14" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_0d4e1050-f7b3-4296-9f16-210357123782" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7a6d8a8c-e290-4206-a49b-9b9d3959a035" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_0d4e1050-f7b3-4296-9f16-210357123782" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_8f72ef15-d99e-4124-b060-f821f8761af4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7a6d8a8c-e290-4206-a49b-9b9d3959a035" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_8f72ef15-d99e-4124-b060-f821f8761af4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_03cd4f56-c532-4465-b465-840ed8daa954" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_8f72ef15-d99e-4124-b060-f821f8761af4" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_03cd4f56-c532-4465-b465-840ed8daa954" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_d867160a-c1ed-49f8-bbb3-74424477d281" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_8f72ef15-d99e-4124-b060-f821f8761af4" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_d867160a-c1ed-49f8-bbb3-74424477d281" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_6a27ab25-5e44-4524-a67e-c9b07b463894" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_8f72ef15-d99e-4124-b060-f821f8761af4" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_6a27ab25-5e44-4524-a67e-c9b07b463894" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_0fa51e2f-f5a2-4601-8ff6-30fc0682d35c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_8f72ef15-d99e-4124-b060-f821f8761af4" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_0fa51e2f-f5a2-4601-8ff6-30fc0682d35c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_9a80bb83-0eb4-436a-8883-f2104de3ef80" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_651015ba-a688-4c27-a70a-37ab7ff3f5bc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7a6d8a8c-e290-4206-a49b-9b9d3959a035" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_651015ba-a688-4c27-a70a-37ab7ff3f5bc" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_21381455-0478-49a1-b00f-e36f26a853fe" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_651015ba-a688-4c27-a70a-37ab7ff3f5bc" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_21381455-0478-49a1-b00f-e36f26a853fe" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_4bb6e96b-8fa9-43ba-9435-d6ea43e7d4dd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_651015ba-a688-4c27-a70a-37ab7ff3f5bc" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_4bb6e96b-8fa9-43ba-9435-d6ea43e7d4dd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_0c84b608-269b-4e04-8e54-35422619fb8f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_651015ba-a688-4c27-a70a-37ab7ff3f5bc" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_0c84b608-269b-4e04-8e54-35422619fb8f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_9e29245b-cca8-45cb-bdbf-a3d2168f9cf0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_651015ba-a688-4c27-a70a-37ab7ff3f5bc" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_9e29245b-cca8-45cb-bdbf-a3d2168f9cf0" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_e519ecf8-d366-4d6d-be2e-34e9a1562243" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.cardinal.com/role/ShareBasedCompensationScheduleofAllTransactionsRelatedtoPerformanceShareUnitsUnderthePlansDetails" xlink:type="simple" xlink:href="cah-20241231.xsd#ShareBasedCompensationScheduleofAllTransactionsRelatedtoPerformanceShareUnitsUnderthePlansDetails"/>
  <link:definitionLink xlink:role="http://www.cardinal.com/role/ShareBasedCompensationScheduleofAllTransactionsRelatedtoPerformanceShareUnitsUnderthePlansDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_cda91fa8-1c38-40bc-8bca-aea4b45f5160" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_d7e5a5cc-8cd9-433c-9cb5-bc10b330d89b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_cda91fa8-1c38-40bc-8bca-aea4b45f5160" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_d7e5a5cc-8cd9-433c-9cb5-bc10b330d89b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_2986cae0-53b7-4b0d-98ab-c3de20ade0f1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_d7e5a5cc-8cd9-433c-9cb5-bc10b330d89b" xlink:to="loc_us-gaap_AwardTypeAxis_2986cae0-53b7-4b0d-98ab-c3de20ade0f1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_2986cae0-53b7-4b0d-98ab-c3de20ade0f1_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_2986cae0-53b7-4b0d-98ab-c3de20ade0f1" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_2986cae0-53b7-4b0d-98ab-c3de20ade0f1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_bbc0cbe7-e6f3-4d38-8465-854477045251" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_2986cae0-53b7-4b0d-98ab-c3de20ade0f1" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_bbc0cbe7-e6f3-4d38-8465-854477045251" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PerformanceSharesMember_3d18b1ff-b9f0-43f7-bf1a-b75a1563a0e2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PerformanceSharesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_bbc0cbe7-e6f3-4d38-8465-854477045251" xlink:to="loc_us-gaap_PerformanceSharesMember_3d18b1ff-b9f0-43f7-bf1a-b75a1563a0e2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage_63adab9d-5745-45bd-aaa1-73f99f98af2c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_cda91fa8-1c38-40bc-8bca-aea4b45f5160" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage_63adab9d-5745-45bd-aaa1-73f99f98af2c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_ed23db49-ef37-463f-9254-827c9c130b48" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_cda91fa8-1c38-40bc-8bca-aea4b45f5160" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_ed23db49-ef37-463f-9254-827c9c130b48" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_b41c1af6-ee13-45ed-a005-8a4fc8029140" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_ed23db49-ef37-463f-9254-827c9c130b48" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_b41c1af6-ee13-45ed-a005-8a4fc8029140" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_a9c47225-3a08-4c9c-90f9-37a05cf183e8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_ed23db49-ef37-463f-9254-827c9c130b48" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_a9c47225-3a08-4c9c-90f9-37a05cf183e8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_d15fe11a-2092-4fb2-a06d-bfe81918c382" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_ed23db49-ef37-463f-9254-827c9c130b48" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_d15fe11a-2092-4fb2-a06d-bfe81918c382" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_c8c02e59-e05b-44f1-b64c-e15f384dbdb6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_ed23db49-ef37-463f-9254-827c9c130b48" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_c8c02e59-e05b-44f1-b64c-e15f384dbdb6" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_fbed6beb-8e3c-4ab9-a08f-a96d8885d484" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_facf84ef-b4d8-435d-8174-a2b7c011154a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_cda91fa8-1c38-40bc-8bca-aea4b45f5160" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_facf84ef-b4d8-435d-8174-a2b7c011154a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_7cfbb1a2-f816-4609-87c2-81a4c2dfbdd4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_facf84ef-b4d8-435d-8174-a2b7c011154a" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_7cfbb1a2-f816-4609-87c2-81a4c2dfbdd4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_1d3802ec-ce5f-4f14-9b54-f550e7d93478" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_facf84ef-b4d8-435d-8174-a2b7c011154a" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_1d3802ec-ce5f-4f14-9b54-f550e7d93478" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_c81425d1-5f15-4a07-96aa-d683fd080d35" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_facf84ef-b4d8-435d-8174-a2b7c011154a" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_c81425d1-5f15-4a07-96aa-d683fd080d35" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_a5eabc43-b0c5-4a7c-8953-e633f85543ab" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_facf84ef-b4d8-435d-8174-a2b7c011154a" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_a5eabc43-b0c5-4a7c-8953-e633f85543ab" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_28f3428c-54d9-433c-97c9-87677dd11fdd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_f43315e4-3d0c-4df8-9045-5998f0c884b9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_cda91fa8-1c38-40bc-8bca-aea4b45f5160" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_f43315e4-3d0c-4df8-9045-5998f0c884b9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_ae959ca8-da84-4c61-b83c-16f64bc3d783" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_cda91fa8-1c38-40bc-8bca-aea4b45f5160" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_ae959ca8-da84-4c61-b83c-16f64bc3d783" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_3ba5d3df-3df9-4b3f-88ea-27063cd60b81" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_cda91fa8-1c38-40bc-8bca-aea4b45f5160" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_3ba5d3df-3df9-4b3f-88ea-27063cd60b81" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://fasb.org/us-gaap/role/eedm/ExtensibleEnumerationLists" xlink:type="simple" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-roles-2024.xsd#eedm"/>
  <link:definitionLink xlink:role="http://fasb.org/us-gaap/role/eedm/ExtensibleEnumerationLists" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementAbstract"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnSalesOfAssetsAndAssetImpairmentCharges" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GainLossOnSalesOfAssetsAndAssetImpairmentCharges"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementAbstract" xlink:to="loc_us-gaap_GainLossOnSalesOfAssetsAndAssetImpairmentCharges" xlink:type="arc" order="691"/>
  </link:definitionLink>
</link:linkbase>
