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

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2025 Workiva-->
<!--r:87a6d082-bd9b-47e2-9de5-74bc7b01d3ad,g:f9105739-e374-4856-86c9-ff5ddb37c14b-->
<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.luxfer.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFCHANGESINEQUITYUNAUDITED" xlink:type="simple" xlink:href="lxfr-20250629.xsd#CONDENSEDCONSOLIDATEDSTATEMENTSOFCHANGESINEQUITYUNAUDITED"/>
  <link:definitionLink xlink:role="http://www.luxfer.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFCHANGESINEQUITYUNAUDITED" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_767be637-be20-47d5-840b-fc65b7a62b3d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_32e2ecb1-53c0-4196-ad06-b729c0f6d5c1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_767be637-be20-47d5-840b-fc65b7a62b3d" xlink:to="loc_us-gaap_StatementTable_32e2ecb1-53c0-4196-ad06-b729c0f6d5c1" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_af6ceff1-f49a-4bd9-bce9-3be831c7e52c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_32e2ecb1-53c0-4196-ad06-b729c0f6d5c1" xlink:to="loc_us-gaap_StatementClassOfStockAxis_af6ceff1-f49a-4bd9-bce9-3be831c7e52c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_af6ceff1-f49a-4bd9-bce9-3be831c7e52c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_af6ceff1-f49a-4bd9-bce9-3be831c7e52c" xlink:to="loc_us-gaap_ClassOfStockDomain_af6ceff1-f49a-4bd9-bce9-3be831c7e52c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_12b82bed-24a4-41b6-b8d6-62593daa7b9f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_af6ceff1-f49a-4bd9-bce9-3be831c7e52c" xlink:to="loc_us-gaap_ClassOfStockDomain_12b82bed-24a4-41b6-b8d6-62593daa7b9f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_OrdinarySharesMember_071a173f-4c22-4bb4-bb98-44fcb4710a40" xlink:href="lxfr-20250629.xsd#lxfr_OrdinarySharesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_12b82bed-24a4-41b6-b8d6-62593daa7b9f" xlink:to="loc_lxfr_OrdinarySharesMember_071a173f-4c22-4bb4-bb98-44fcb4710a40" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_e96936a6-4d4a-40fd-8ae7-b204965122f0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_32e2ecb1-53c0-4196-ad06-b729c0f6d5c1" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_e96936a6-4d4a-40fd-8ae7-b204965122f0" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_e96936a6-4d4a-40fd-8ae7-b204965122f0_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_e96936a6-4d4a-40fd-8ae7-b204965122f0" xlink:to="loc_us-gaap_EquityComponentDomain_e96936a6-4d4a-40fd-8ae7-b204965122f0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_9b13d4f7-7c04-4ebb-846c-8f902e2c13eb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_e96936a6-4d4a-40fd-8ae7-b204965122f0" xlink:to="loc_us-gaap_EquityComponentDomain_9b13d4f7-7c04-4ebb-846c-8f902e2c13eb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_b700665f-1cd4-4888-991a-8d7a2a67de3d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_9b13d4f7-7c04-4ebb-846c-8f902e2c13eb" xlink:to="loc_us-gaap_CommonStockMember_b700665f-1cd4-4888-991a-8d7a2a67de3d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember_c26dedd0-9784-4b0a-9cb8-e161237ae34e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdditionalPaidInCapitalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_9b13d4f7-7c04-4ebb-846c-8f902e2c13eb" xlink:to="loc_us-gaap_AdditionalPaidInCapitalMember_c26dedd0-9784-4b0a-9cb8-e161237ae34e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockCommonMember_a6ea084d-acef-4bca-9aa3-63eb9eb2d4fb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TreasuryStockCommonMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_9b13d4f7-7c04-4ebb-846c-8f902e2c13eb" xlink:to="loc_us-gaap_TreasuryStockCommonMember_a6ea084d-acef-4bca-9aa3-63eb9eb2d4fb" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_OwnSharesHeldByEmployeeStockOwnershipPlanMember_34accdcf-9370-425f-9749-522fab36e5ac" xlink:href="lxfr-20250629.xsd#lxfr_OwnSharesHeldByEmployeeStockOwnershipPlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_9b13d4f7-7c04-4ebb-846c-8f902e2c13eb" xlink:to="loc_lxfr_OwnSharesHeldByEmployeeStockOwnershipPlanMember_34accdcf-9370-425f-9749-522fab36e5ac" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsMember_d2fabe10-af34-4a13-be43-9f742a7925d5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RetainedEarningsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_9b13d4f7-7c04-4ebb-846c-8f902e2c13eb" xlink:to="loc_us-gaap_RetainedEarningsMember_d2fabe10-af34-4a13-be43-9f742a7925d5" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_e733cde1-0140-4d8d-b8a5-3d99af940e1e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_9b13d4f7-7c04-4ebb-846c-8f902e2c13eb" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_e733cde1-0140-4d8d-b8a5-3d99af940e1e" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_4548d303-79c6-4177-8158-814f65b84fdb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_767be637-be20-47d5-840b-fc65b7a62b3d" xlink:to="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_4548d303-79c6-4177-8158-814f65b84fdb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_07a56fcd-1d5d-447c-a9b8-af5e4274c685" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_4548d303-79c6-4177-8158-814f65b84fdb" xlink:to="loc_us-gaap_StockholdersEquity_07a56fcd-1d5d-447c-a9b8-af5e4274c685" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockCommonShares_8e2add44-f4c0-472e-9694-0bca3c1ac59b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TreasuryStockCommonShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_4548d303-79c6-4177-8158-814f65b84fdb" xlink:to="loc_us-gaap_TreasuryStockCommonShares_8e2add44-f4c0-472e-9694-0bca3c1ac59b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharesOutstanding_1796bab8-1d14-4066-a91c-93b44b1cbf1e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_4548d303-79c6-4177-8158-814f65b84fdb" xlink:to="loc_us-gaap_SharesOutstanding_1796bab8-1d14-4066-a91c-93b44b1cbf1e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_5c06b8f5-75a6-4c35-8cca-ebb6bf421d08" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_4548d303-79c6-4177-8158-814f65b84fdb" xlink:to="loc_us-gaap_NetIncomeLoss_5c06b8f5-75a6-4c35-8cca-ebb6bf421d08" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_e18b483f-7ad9-4236-89f9-0dd39ba63104" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_4548d303-79c6-4177-8158-814f65b84fdb" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_e18b483f-7ad9-4236-89f9-0dd39ba63104" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsCommonStock_05762ad0-03c8-4a96-a317-ee198a782971" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DividendsCommonStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_4548d303-79c6-4177-8158-814f65b84fdb" xlink:to="loc_us-gaap_DividendsCommonStock_05762ad0-03c8-4a96-a317-ee198a782971" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_13dbe18c-0216-4248-bd41-f0a364297d6b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_4548d303-79c6-4177-8158-814f65b84fdb" xlink:to="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_13dbe18c-0216-4248-bd41-f0a364297d6b" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchasedDuringPeriodShares_4558dbfe-9713-4ab4-9ef0-0735049eb3c3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockRepurchasedDuringPeriodShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_4548d303-79c6-4177-8158-814f65b84fdb" xlink:to="loc_us-gaap_StockRepurchasedDuringPeriodShares_4558dbfe-9713-4ab4-9ef0-0735049eb3c3" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_1ed06a44-9e53-4ade-a679-267c56c31d89" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TreasuryStockValueAcquiredCostMethod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_4548d303-79c6-4177-8158-814f65b84fdb" xlink:to="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_1ed06a44-9e53-4ade-a679-267c56c31d89" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_StockIssuedDuringPeriodValueTreasuryStockReissuedToSatisfyShareBasedCompensation_c5ac4af6-c934-44a8-a33d-0e4a9366c49b" xlink:href="lxfr-20250629.xsd#lxfr_StockIssuedDuringPeriodValueTreasuryStockReissuedToSatisfyShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_4548d303-79c6-4177-8158-814f65b84fdb" xlink:to="loc_lxfr_StockIssuedDuringPeriodValueTreasuryStockReissuedToSatisfyShareBasedCompensation_c5ac4af6-c934-44a8-a33d-0e4a9366c49b" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_05f50784-f6c0-4c32-b3c2-f235d5b86228" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_4548d303-79c6-4177-8158-814f65b84fdb" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_05f50784-f6c0-4c32-b3c2-f235d5b86228" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_StockIssuedDuringPeriodValueSharesFromEmployeeStockOwnershipPlanToSatisfyShareBasedCompensation_cc48771e-37d1-4c32-b923-df68614d81c1" xlink:href="lxfr-20250629.xsd#lxfr_StockIssuedDuringPeriodValueSharesFromEmployeeStockOwnershipPlanToSatisfyShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_4548d303-79c6-4177-8158-814f65b84fdb" xlink:to="loc_lxfr_StockIssuedDuringPeriodValueSharesFromEmployeeStockOwnershipPlanToSatisfyShareBasedCompensation_cc48771e-37d1-4c32-b923-df68614d81c1" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_StockIssuedDuringPeriodSharesSharesFromEmployeeStockOwnershipPlanToSatisfyShareBasedCompensation_9ddb492b-fca7-490f-b707-9cc8be3d318b" xlink:href="lxfr-20250629.xsd#lxfr_StockIssuedDuringPeriodSharesSharesFromEmployeeStockOwnershipPlanToSatisfyShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_4548d303-79c6-4177-8158-814f65b84fdb" xlink:to="loc_lxfr_StockIssuedDuringPeriodSharesSharesFromEmployeeStockOwnershipPlanToSatisfyShareBasedCompensation_9ddb492b-fca7-490f-b707-9cc8be3d318b" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_f93370d8-d48b-4306-b847-f8777d786030" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquity"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockCommonShares_d2da49bd-1b7e-45c0-a2c4-50c3acc0a18c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TreasuryStockCommonShares"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharesOutstanding_6905b870-628c-4917-bb69-8a17ed8d00b1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharesOutstanding"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.luxfer.com/role/EarningspershareDetails" xlink:type="simple" xlink:href="lxfr-20250629.xsd#EarningspershareDetails"/>
  <link:definitionLink xlink:role="http://www.luxfer.com/role/EarningspershareDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockLineItems_d9dfa064-d858-4407-b627-4aa762e4637b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfStockByClassTable_35ecde34-bf28-44fd-bfb2-25d9bbad1507" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfStockByClassTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ClassOfStockLineItems_d9dfa064-d858-4407-b627-4aa762e4637b" xlink:to="loc_us-gaap_ScheduleOfStockByClassTable_35ecde34-bf28-44fd-bfb2-25d9bbad1507" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_f37f946a-98de-40aa-8d39-7d283c2d0277" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_35ecde34-bf28-44fd-bfb2-25d9bbad1507" xlink:to="loc_us-gaap_StatementClassOfStockAxis_f37f946a-98de-40aa-8d39-7d283c2d0277" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_f37f946a-98de-40aa-8d39-7d283c2d0277_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_f37f946a-98de-40aa-8d39-7d283c2d0277" xlink:to="loc_us-gaap_ClassOfStockDomain_f37f946a-98de-40aa-8d39-7d283c2d0277_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_a75dcea1-d9fa-4809-a396-87ec16974ca3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_f37f946a-98de-40aa-8d39-7d283c2d0277" xlink:to="loc_us-gaap_ClassOfStockDomain_a75dcea1-d9fa-4809-a396-87ec16974ca3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_OrdinarySharesMember_67e65697-25d9-4bcd-afe1-2c122a8c4e30" xlink:href="lxfr-20250629.xsd#lxfr_OrdinarySharesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_a75dcea1-d9fa-4809-a396-87ec16974ca3" xlink:to="loc_lxfr_OrdinarySharesMember_67e65697-25d9-4bcd-afe1-2c122a8c4e30" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasicAbstract_340a0f70-4113-4f6d-8d39-72dd2d48e573" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersBasicAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_d9dfa064-d858-4407-b627-4aa762e4637b" xlink:to="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasicAbstract_340a0f70-4113-4f6d-8d39-72dd2d48e573" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperations_218676f4-6c05-4124-aa03-67b2a7112a1a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromContinuingOperations"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasicAbstract_340a0f70-4113-4f6d-8d39-72dd2d48e573" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperations_218676f4-6c05-4124-aa03-67b2a7112a1a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity_45229430-2e35-495d-86c5-cbceb64b1fe2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasicAbstract_340a0f70-4113-4f6d-8d39-72dd2d48e573" xlink:to="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity_45229430-2e35-495d-86c5-cbceb64b1fe2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_8e79d574-110a-487c-bfb7-cee63943d2b3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasicAbstract_340a0f70-4113-4f6d-8d39-72dd2d48e573" xlink:to="loc_us-gaap_NetIncomeLoss_8e79d574-110a-487c-bfb7-cee63943d2b3" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockParOrStatedValuePerShare_d4df40ad-d8b5-43e7-bf95-b4df20b4da9f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockParOrStatedValuePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_d9dfa064-d858-4407-b627-4aa762e4637b" xlink:to="loc_us-gaap_CommonStockParOrStatedValuePerShare_d4df40ad-d8b5-43e7-bf95-b4df20b4da9f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingDilutedDisclosureItemsAbstract_6d3bc119-91a7-45ce-8033-18887c77874e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingDilutedDisclosureItemsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_d9dfa064-d858-4407-b627-4aa762e4637b" xlink:to="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingDilutedDisclosureItemsAbstract_6d3bc119-91a7-45ce-8033-18887c77874e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_77018c4b-1107-4a35-8872-b2fb6a13947d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingDilutedDisclosureItemsAbstract_6d3bc119-91a7-45ce-8033-18887c77874e" xlink:to="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_77018c4b-1107-4a35-8872-b2fb6a13947d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustment_a8fa4e1b-4389-4a43-a4a8-0827b02b193e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingDilutedDisclosureItemsAbstract_6d3bc119-91a7-45ce-8033-18887c77874e" xlink:to="loc_us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustment_a8fa4e1b-4389-4a43-a4a8-0827b02b193e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_76d1145f-4333-47ee-ae01-1de53ba391c6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingDilutedDisclosureItemsAbstract_6d3bc119-91a7-45ce-8033-18887c77874e" xlink:to="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_76d1145f-4333-47ee-ae01-1de53ba391c6" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareBasicTwoClassMethodAbstract_9b0e40a3-7a3f-4a19-8092-db4729367b7c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EarningsPerShareBasicTwoClassMethodAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_d9dfa064-d858-4407-b627-4aa762e4637b" xlink:to="loc_us-gaap_EarningsPerShareBasicTwoClassMethodAbstract_9b0e40a3-7a3f-4a19-8092-db4729367b7c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsPerBasicShare_30ca3b2f-5b0b-4d80-bb02-c229accf58dd" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromContinuingOperationsPerBasicShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareBasicTwoClassMethodAbstract_9b0e40a3-7a3f-4a19-8092-db4729367b7c" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsPerBasicShare_30ca3b2f-5b0b-4d80-bb02-c229accf58dd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare_3c6638fc-0d30-4288-895e-b2038b547e22" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareBasicTwoClassMethodAbstract_9b0e40a3-7a3f-4a19-8092-db4729367b7c" xlink:to="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare_3c6638fc-0d30-4288-895e-b2038b547e22" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareBasic_7bdc75e3-0d95-4530-a61d-64e2d9f200e3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EarningsPerShareBasic"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareBasicTwoClassMethodAbstract_9b0e40a3-7a3f-4a19-8092-db4729367b7c" xlink:to="loc_us-gaap_EarningsPerShareBasic_7bdc75e3-0d95-4530-a61d-64e2d9f200e3" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare_14ca7951-ee5d-4bd5-815d-6e80127c56fc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareBasicTwoClassMethodAbstract_9b0e40a3-7a3f-4a19-8092-db4729367b7c" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare_14ca7951-ee5d-4bd5-815d-6e80127c56fc" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare_232177c3-6f49-43b3-9f94-1b770c92d0ee" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareBasicTwoClassMethodAbstract_9b0e40a3-7a3f-4a19-8092-db4729367b7c" xlink:to="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare_232177c3-6f49-43b3-9f94-1b770c92d0ee" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareDiluted_5fc96745-ea10-44e6-ac55-73e7888dcd64" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EarningsPerShareDiluted"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareBasicTwoClassMethodAbstract_9b0e40a3-7a3f-4a19-8092-db4729367b7c" xlink:to="loc_us-gaap_EarningsPerShareDiluted_5fc96745-ea10-44e6-ac55-73e7888dcd64" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.luxfer.com/role/NetSalesDetails" xlink:type="simple" xlink:href="lxfr-20250629.xsd#NetSalesDetails"/>
  <link:definitionLink xlink:role="http://www.luxfer.com/role/NetSalesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueLineItems_49d12f35-194c-4ae1-aa9d-dd4c7d2655d4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisaggregationOfRevenueLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueTable_fe8f328e-17ad-464a-b38c-93c74d95512f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisaggregationOfRevenueTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_49d12f35-194c-4ae1-aa9d-dd4c7d2655d4" xlink:to="loc_us-gaap_DisaggregationOfRevenueTable_fe8f328e-17ad-464a-b38c-93c74d95512f" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_a4e7244a-6fd3-482d-960b-33027376af70" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_fe8f328e-17ad-464a-b38c-93c74d95512f" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_a4e7244a-6fd3-482d-960b-33027376af70" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_a4e7244a-6fd3-482d-960b-33027376af70_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_a4e7244a-6fd3-482d-960b-33027376af70" xlink:to="loc_us-gaap_SegmentDomain_a4e7244a-6fd3-482d-960b-33027376af70_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_38e37df4-90c8-444c-81ae-1c743aea8fb0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_a4e7244a-6fd3-482d-960b-33027376af70" xlink:to="loc_us-gaap_SegmentDomain_38e37df4-90c8-444c-81ae-1c743aea8fb0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_GasCylindersSegmentMember_f6774b82-23e5-44ad-b001-c5b3e1e44a82" xlink:href="lxfr-20250629.xsd#lxfr_GasCylindersSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_38e37df4-90c8-444c-81ae-1c743aea8fb0" xlink:to="loc_lxfr_GasCylindersSegmentMember_f6774b82-23e5-44ad-b001-c5b3e1e44a82" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_ElektronSegmentMember_4da77579-c61e-42a1-b280-59945b80ca7e" xlink:href="lxfr-20250629.xsd#lxfr_ElektronSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_38e37df4-90c8-444c-81ae-1c743aea8fb0" xlink:to="loc_lxfr_ElektronSegmentMember_4da77579-c61e-42a1-b280-59945b80ca7e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_GraphicArtsMember_5aab70f0-a0e9-4fb0-ba73-878454575d28" xlink:href="lxfr-20250629.xsd#lxfr_GraphicArtsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_38e37df4-90c8-444c-81ae-1c743aea8fb0" xlink:to="loc_lxfr_GraphicArtsMember_5aab70f0-a0e9-4fb0-ba73-878454575d28" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_86cca855-1347-49ec-a606-895e14a26c27" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_fe8f328e-17ad-464a-b38c-93c74d95512f" xlink:to="loc_srt_ProductOrServiceAxis_86cca855-1347-49ec-a606-895e14a26c27" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_86cca855-1347-49ec-a606-895e14a26c27_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_86cca855-1347-49ec-a606-895e14a26c27" xlink:to="loc_srt_ProductsAndServicesDomain_86cca855-1347-49ec-a606-895e14a26c27_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_06862bf4-2129-43c2-befd-b44833dd55f8" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_86cca855-1347-49ec-a606-895e14a26c27" xlink:to="loc_srt_ProductsAndServicesDomain_06862bf4-2129-43c2-befd-b44833dd55f8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_DefenseFirstResponseAndHealthcareMember_2840b9bb-772a-4898-b44c-0fae4546dff4" xlink:href="lxfr-20250629.xsd#lxfr_DefenseFirstResponseAndHealthcareMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_06862bf4-2129-43c2-befd-b44833dd55f8" xlink:to="loc_lxfr_DefenseFirstResponseAndHealthcareMember_2840b9bb-772a-4898-b44c-0fae4546dff4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_TransportationMember_52b671d7-0756-4676-a9db-9e5879ba0547" xlink:href="lxfr-20250629.xsd#lxfr_TransportationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_06862bf4-2129-43c2-befd-b44833dd55f8" xlink:to="loc_lxfr_TransportationMember_52b671d7-0756-4676-a9db-9e5879ba0547" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_SpecialityIndustrialMember_43c4d275-cdcd-4918-9ae9-e1d716839d7f" xlink:href="lxfr-20250629.xsd#lxfr_SpecialityIndustrialMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_06862bf4-2129-43c2-befd-b44833dd55f8" xlink:to="loc_lxfr_SpecialityIndustrialMember_43c4d275-cdcd-4918-9ae9-e1d716839d7f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_db41834f-d490-4143-88b2-ce0fc53eddd8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_49d12f35-194c-4ae1-aa9d-dd4c7d2655d4" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_db41834f-d490-4143-88b2-ce0fc53eddd8" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.luxfer.com/role/RestructuringScheduleofRestructuringRelatedCostsDetails" xlink:type="simple" xlink:href="lxfr-20250629.xsd#RestructuringScheduleofRestructuringRelatedCostsDetails"/>
  <link:definitionLink xlink:role="http://www.luxfer.com/role/RestructuringScheduleofRestructuringRelatedCostsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringCostAndReserveLineItems_6df0b767-7ae0-4a34-b9dd-1a39a9efaafb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestructuringCostAndReserveLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_7b0851ee-55b0-454e-902d-be96cb33e5f1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfRestructuringAndRelatedCostsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_6df0b767-7ae0-4a34-b9dd-1a39a9efaafb" xlink:to="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_7b0851ee-55b0-454e-902d-be96cb33e5f1" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_20ea6272-9ec9-4b61-9d8c-85a036b1ef21" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_7b0851ee-55b0-454e-902d-be96cb33e5f1" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_20ea6272-9ec9-4b61-9d8c-85a036b1ef21" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_20ea6272-9ec9-4b61-9d8c-85a036b1ef21_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_20ea6272-9ec9-4b61-9d8c-85a036b1ef21" xlink:to="loc_us-gaap_SegmentDomain_20ea6272-9ec9-4b61-9d8c-85a036b1ef21_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_4b135e3e-afa7-4cd3-880b-43b7eea16089" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_20ea6272-9ec9-4b61-9d8c-85a036b1ef21" xlink:to="loc_us-gaap_SegmentDomain_4b135e3e-afa7-4cd3-880b-43b7eea16089" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_GasCylindersSegmentMember_d1e62ea4-d10a-4e92-bc07-3e367e074d1e" xlink:href="lxfr-20250629.xsd#lxfr_GasCylindersSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_4b135e3e-afa7-4cd3-880b-43b7eea16089" xlink:to="loc_lxfr_GasCylindersSegmentMember_d1e62ea4-d10a-4e92-bc07-3e367e074d1e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_ElektronSegmentMember_3d8f5cf3-9db4-4de6-9c42-5c3f8a7049f3" xlink:href="lxfr-20250629.xsd#lxfr_ElektronSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_4b135e3e-afa7-4cd3-880b-43b7eea16089" xlink:to="loc_lxfr_ElektronSegmentMember_3d8f5cf3-9db4-4de6-9c42-5c3f8a7049f3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeveranceCosts1_f7865b93-76b3-4653-b208-ff352ecadcde" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SeveranceCosts1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_6df0b767-7ae0-4a34-b9dd-1a39a9efaafb" xlink:to="loc_us-gaap_SeveranceCosts1_f7865b93-76b3-4653-b208-ff352ecadcde" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringReserveAcceleratedDepreciation_239fb50c-9f88-4f13-80c4-7e99d323d185" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestructuringReserveAcceleratedDepreciation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_6df0b767-7ae0-4a34-b9dd-1a39a9efaafb" xlink:to="loc_us-gaap_RestructuringReserveAcceleratedDepreciation_239fb50c-9f88-4f13-80c4-7e99d323d185" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringSettlementAndImpairmentProvisions_d598ca7f-f794-4fcb-8043-f87ac03dcbc1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestructuringSettlementAndImpairmentProvisions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_6df0b767-7ae0-4a34-b9dd-1a39a9efaafb" xlink:to="loc_us-gaap_RestructuringSettlementAndImpairmentProvisions_d598ca7f-f794-4fcb-8043-f87ac03dcbc1" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.luxfer.com/role/AcquisitionanddisposalrelatedcostsAdditionalInformationDetails" xlink:type="simple" xlink:href="lxfr-20250629.xsd#AcquisitionanddisposalrelatedcostsAdditionalInformationDetails"/>
  <link:definitionLink xlink:role="http://www.luxfer.com/role/AcquisitionanddisposalrelatedcostsAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetAcquisitionLineItems_899238e3-f9b5-49a7-ab30-1bacf3ec6d74" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetAcquisitionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetAcquisitionTable_4e89a7c1-33a7-44b5-bd21-ddbfc9c2b965" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetAcquisitionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AssetAcquisitionLineItems_899238e3-f9b5-49a7-ab30-1bacf3ec6d74" xlink:to="loc_us-gaap_AssetAcquisitionTable_4e89a7c1-33a7-44b5-bd21-ddbfc9c2b965" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NatureOfExpenseAxis_44686593-bbda-4cbb-b81c-4138c7251c28" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NatureOfExpenseAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_AssetAcquisitionTable_4e89a7c1-33a7-44b5-bd21-ddbfc9c2b965" xlink:to="loc_us-gaap_NatureOfExpenseAxis_44686593-bbda-4cbb-b81c-4138c7251c28" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterimPeriodCostsNotAllocableDomain_44686593-bbda-4cbb-b81c-4138c7251c28_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterimPeriodCostsNotAllocableDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_NatureOfExpenseAxis_44686593-bbda-4cbb-b81c-4138c7251c28" xlink:to="loc_us-gaap_InterimPeriodCostsNotAllocableDomain_44686593-bbda-4cbb-b81c-4138c7251c28_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterimPeriodCostsNotAllocableDomain_d190b0b9-6511-4fae-bf75-bdc2de0ca499" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterimPeriodCostsNotAllocableDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_NatureOfExpenseAxis_44686593-bbda-4cbb-b81c-4138c7251c28" xlink:to="loc_us-gaap_InterimPeriodCostsNotAllocableDomain_d190b0b9-6511-4fae-bf75-bdc2de0ca499" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_ProfessionalFeesMember_a43a7550-868d-4563-8d6f-faa3967465c1" xlink:href="lxfr-20250629.xsd#lxfr_ProfessionalFeesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InterimPeriodCostsNotAllocableDomain_d190b0b9-6511-4fae-bf75-bdc2de0ca499" xlink:to="loc_lxfr_ProfessionalFeesMember_a43a7550-868d-4563-8d6f-faa3967465c1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_1ff6f864-c32d-401a-936d-172830c50f4c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_AssetAcquisitionTable_4e89a7c1-33a7-44b5-bd21-ddbfc9c2b965" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_1ff6f864-c32d-401a-936d-172830c50f4c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_1ff6f864-c32d-401a-936d-172830c50f4c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_1ff6f864-c32d-401a-936d-172830c50f4c" xlink:to="loc_us-gaap_SegmentDomain_1ff6f864-c32d-401a-936d-172830c50f4c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_72fb2a3f-3fcc-46b5-8574-56655fe0c34c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_1ff6f864-c32d-401a-936d-172830c50f4c" xlink:to="loc_us-gaap_SegmentDomain_72fb2a3f-3fcc-46b5-8574-56655fe0c34c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_GraphicArtsMember_20a6f266-df66-47e6-9873-627d52969624" xlink:href="lxfr-20250629.xsd#lxfr_GraphicArtsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_72fb2a3f-3fcc-46b5-8574-56655fe0c34c" xlink:to="loc_lxfr_GraphicArtsMember_20a6f266-df66-47e6-9873-627d52969624" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_DisposalGroupNotDiscontinuedOperationDisposalCost_485fcd0c-283d-48a6-83f7-9fa732da1376" xlink:href="lxfr-20250629.xsd#lxfr_DisposalGroupNotDiscontinuedOperationDisposalCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetAcquisitionLineItems_899238e3-f9b5-49a7-ab30-1bacf3ec6d74" xlink:to="loc_lxfr_DisposalGroupNotDiscontinuedOperationDisposalCost_485fcd0c-283d-48a6-83f7-9fa732da1376" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupNotDiscontinuedOperationLossGainOnWriteDown_e6836659-001b-4391-b934-11c7340eda2e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupNotDiscontinuedOperationLossGainOnWriteDown"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetAcquisitionLineItems_899238e3-f9b5-49a7-ab30-1bacf3ec6d74" xlink:to="loc_us-gaap_DisposalGroupNotDiscontinuedOperationLossGainOnWriteDown_e6836659-001b-4391-b934-11c7340eda2e" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.luxfer.com/role/SupplementarybalancesheetinformationDetails" xlink:type="simple" xlink:href="lxfr-20250629.xsd#SupplementarybalancesheetinformationDetails"/>
  <link:definitionLink xlink:role="http://www.luxfer.com/role/SupplementarybalancesheetinformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentLineItems_f54855df-6a9b-479b-9284-31a10a297958" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_3645fe6c-bb5b-4f5f-870e-e1b0f2e6eaf4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfPropertyPlantAndEquipmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_f54855df-6a9b-479b-9284-31a10a297958" xlink:to="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_3645fe6c-bb5b-4f5f-870e-e1b0f2e6eaf4" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_20a4ad62-d321-4b6a-bb6c-849e4edb1cf6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_3645fe6c-bb5b-4f5f-870e-e1b0f2e6eaf4" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_20a4ad62-d321-4b6a-bb6c-849e4edb1cf6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_20a4ad62-d321-4b6a-bb6c-849e4edb1cf6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_20a4ad62-d321-4b6a-bb6c-849e4edb1cf6" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_20a4ad62-d321-4b6a-bb6c-849e4edb1cf6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_539cdd1c-3a51-47ac-90d8-6aef0e14bfc9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_20a4ad62-d321-4b6a-bb6c-849e4edb1cf6" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_539cdd1c-3a51-47ac-90d8-6aef0e14bfc9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LandBuildingsAndImprovementsMember_815469cf-12fe-4cd7-ab42-f493178c0591" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LandBuildingsAndImprovementsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_539cdd1c-3a51-47ac-90d8-6aef0e14bfc9" xlink:to="loc_us-gaap_LandBuildingsAndImprovementsMember_815469cf-12fe-4cd7-ab42-f493178c0591" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MachineryAndEquipmentMember_495691f8-7576-460b-bf56-26d3b0ad7a00" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MachineryAndEquipmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_539cdd1c-3a51-47ac-90d8-6aef0e14bfc9" xlink:to="loc_us-gaap_MachineryAndEquipmentMember_495691f8-7576-460b-bf56-26d3b0ad7a00" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConstructionInProgressMember_369d4a26-fd55-4220-88f1-f69ce5dd6534" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConstructionInProgressMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_539cdd1c-3a51-47ac-90d8-6aef0e14bfc9" xlink:to="loc_us-gaap_ConstructionInProgressMember_369d4a26-fd55-4220-88f1-f69ce5dd6534" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_779cdc15-f391-485e-a9c5-cfcbd82871c7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_3645fe6c-bb5b-4f5f-870e-e1b0f2e6eaf4" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_779cdc15-f391-485e-a9c5-cfcbd82871c7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_779cdc15-f391-485e-a9c5-cfcbd82871c7_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_779cdc15-f391-485e-a9c5-cfcbd82871c7" xlink:to="loc_us-gaap_RelatedPartyDomain_779cdc15-f391-485e-a9c5-cfcbd82871c7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_0e09e08a-4973-4d6a-b6c8-2699474be7a5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_779cdc15-f391-485e-a9c5-cfcbd82871c7" xlink:to="loc_us-gaap_RelatedPartyDomain_0e09e08a-4973-4d6a-b6c8-2699474be7a5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyMember_73c5a057-9fe6-477e-bede-7f7dc31a09b0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_0e09e08a-4973-4d6a-b6c8-2699474be7a5" xlink:to="loc_us-gaap_RelatedPartyMember_73c5a057-9fe6-477e-bede-7f7dc31a09b0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NonrelatedPartyMember_e0f30a32-1c35-40e8-8aef-8a4434fd36de" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NonrelatedPartyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_0e09e08a-4973-4d6a-b6c8-2699474be7a5" xlink:to="loc_us-gaap_NonrelatedPartyMember_e0f30a32-1c35-40e8-8aef-8a4434fd36de" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsReceivableNetAbstract_37028096-4cd1-4712-9c88-1f7739bfa9b8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsReceivableNetAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_f54855df-6a9b-479b-9284-31a10a297958" xlink:to="loc_us-gaap_AccountsReceivableNetAbstract_37028096-4cd1-4712-9c88-1f7739bfa9b8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsReceivableNetCurrent_621d8b80-50fd-4ded-8e8e-d9358601ab1c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsReceivableNetCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsReceivableNetAbstract_37028096-4cd1-4712-9c88-1f7739bfa9b8" xlink:to="loc_us-gaap_AccountsReceivableNetCurrent_621d8b80-50fd-4ded-8e8e-d9358601ab1c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherReceivablesNetCurrent_52f40e16-5a3f-4116-8386-4ecc2e4601a0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherReceivablesNetCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsReceivableNetAbstract_37028096-4cd1-4712-9c88-1f7739bfa9b8" xlink:to="loc_us-gaap_OtherReceivablesNetCurrent_52f40e16-5a3f-4116-8386-4ecc2e4601a0" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetsCurrent_dde03642-1616-44a0-b868-53817a432f93" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeAssetsCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsReceivableNetAbstract_37028096-4cd1-4712-9c88-1f7739bfa9b8" xlink:to="loc_us-gaap_DerivativeAssetsCurrent_dde03642-1616-44a0-b868-53817a432f93" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReceivablesNetCurrent_f495c104-f24d-4a48-8c84-af06c849121d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReceivablesNetCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsReceivableNetAbstract_37028096-4cd1-4712-9c88-1f7739bfa9b8" xlink:to="loc_us-gaap_ReceivablesNetCurrent_f495c104-f24d-4a48-8c84-af06c849121d" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryNetAbstract_3e0347a8-f0e2-4eb0-8e62-74a27ef754dd" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InventoryNetAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_f54855df-6a9b-479b-9284-31a10a297958" xlink:to="loc_us-gaap_InventoryNetAbstract_3e0347a8-f0e2-4eb0-8e62-74a27ef754dd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryRawMaterialsAndSuppliesNetOfReserves_65629e0b-7e3e-45ee-a02d-fbdd978723ff" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InventoryRawMaterialsAndSuppliesNetOfReserves"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InventoryNetAbstract_3e0347a8-f0e2-4eb0-8e62-74a27ef754dd" xlink:to="loc_us-gaap_InventoryRawMaterialsAndSuppliesNetOfReserves_65629e0b-7e3e-45ee-a02d-fbdd978723ff" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryWorkInProcessNetOfReserves_bd311165-9669-4064-8d0e-71b61130dd2c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InventoryWorkInProcessNetOfReserves"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InventoryNetAbstract_3e0347a8-f0e2-4eb0-8e62-74a27ef754dd" xlink:to="loc_us-gaap_InventoryWorkInProcessNetOfReserves_bd311165-9669-4064-8d0e-71b61130dd2c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryFinishedGoodsNetOfReserves_d68ba06a-88dc-4758-bace-de045562c655" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InventoryFinishedGoodsNetOfReserves"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InventoryNetAbstract_3e0347a8-f0e2-4eb0-8e62-74a27ef754dd" xlink:to="loc_us-gaap_InventoryFinishedGoodsNetOfReserves_d68ba06a-88dc-4758-bace-de045562c655" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryNet_da1e38f1-83c7-4297-a10e-c58c2525db4d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InventoryNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InventoryNetAbstract_3e0347a8-f0e2-4eb0-8e62-74a27ef754dd" xlink:to="loc_us-gaap_InventoryNet_da1e38f1-83c7-4297-a10e-c58c2525db4d" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentAbstract_bb3e5d83-adbf-485c-ba17-057d1e82b368" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_f54855df-6a9b-479b-9284-31a10a297958" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentAbstract_bb3e5d83-adbf-485c-ba17-057d1e82b368" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentGross_efd82d56-2b34-4a5d-b808-10708ad03ba6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentAbstract_bb3e5d83-adbf-485c-ba17-057d1e82b368" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentGross_efd82d56-2b34-4a5d-b808-10708ad03ba6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_0b9e49df-b891-4db3-966a-9c4ca51a16f8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentAbstract_bb3e5d83-adbf-485c-ba17-057d1e82b368" xlink:to="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_0b9e49df-b891-4db3-966a-9c4ca51a16f8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_6e38ae75-c5fc-41d0-8056-5d3d3f356236" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentAbstract_bb3e5d83-adbf-485c-ba17-057d1e82b368" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentNet_6e38ae75-c5fc-41d0-8056-5d3d3f356236" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherLiabilitiesCurrentAbstract_49610966-ee1a-44af-82e9-4f5b94fc0e6f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherLiabilitiesCurrentAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_f54855df-6a9b-479b-9284-31a10a297958" xlink:to="loc_us-gaap_OtherLiabilitiesCurrentAbstract_49610966-ee1a-44af-82e9-4f5b94fc0e6f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringReserveCurrent_f16c2dfe-1da8-4955-99d1-c33a7ab9a754" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestructuringReserveCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherLiabilitiesCurrentAbstract_49610966-ee1a-44af-82e9-4f5b94fc0e6f" xlink:to="loc_us-gaap_RestructuringReserveCurrent_f16c2dfe-1da8-4955-99d1-c33a7ab9a754" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_CurrentProvisions_09ea94a9-ff5f-4cea-a964-9f407323a732" xlink:href="lxfr-20250629.xsd#lxfr_CurrentProvisions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherLiabilitiesCurrentAbstract_49610966-ee1a-44af-82e9-4f5b94fc0e6f" xlink:to="loc_lxfr_CurrentProvisions_09ea94a9-ff5f-4cea-a964-9f407323a732" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesSubjectToCompromiseEnvironmentalContingencies_5ca53f44-0951-4b4b-9cdb-6bff49613465" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesSubjectToCompromiseEnvironmentalContingencies"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherLiabilitiesCurrentAbstract_49610966-ee1a-44af-82e9-4f5b94fc0e6f" xlink:to="loc_us-gaap_LiabilitiesSubjectToCompromiseEnvironmentalContingencies_5ca53f44-0951-4b4b-9cdb-6bff49613465" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilitiesCurrent_35a4f8a9-61ae-4e12-96cf-667a2043f831" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeLiabilitiesCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherLiabilitiesCurrentAbstract_49610966-ee1a-44af-82e9-4f5b94fc0e6f" xlink:to="loc_us-gaap_DerivativeLiabilitiesCurrent_35a4f8a9-61ae-4e12-96cf-667a2043f831" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseLiabilityCurrent_f2743db8-4b7b-4ad1-b283-29b7fa51cd6e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseLiabilityCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherLiabilitiesCurrentAbstract_49610966-ee1a-44af-82e9-4f5b94fc0e6f" xlink:to="loc_us-gaap_OperatingLeaseLiabilityCurrent_f2743db8-4b7b-4ad1-b283-29b7fa51cd6e" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherSundryLiabilitiesCurrent_44975ff3-7c94-4cbd-831c-3663aa0adae9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherSundryLiabilitiesCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherLiabilitiesCurrentAbstract_49610966-ee1a-44af-82e9-4f5b94fc0e6f" xlink:to="loc_us-gaap_OtherSundryLiabilitiesCurrent_44975ff3-7c94-4cbd-831c-3663aa0adae9" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherLiabilitiesCurrent_80c75f50-3294-4d30-a8c6-137e37269ad4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherLiabilitiesCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherLiabilitiesCurrentAbstract_49610966-ee1a-44af-82e9-4f5b94fc0e6f" xlink:to="loc_us-gaap_OtherLiabilitiesCurrent_80c75f50-3294-4d30-a8c6-137e37269ad4" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList_d0766e23-f269-4ab2-b36c-d5b979575de5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherLiabilitiesCurrentAbstract_49610966-ee1a-44af-82e9-4f5b94fc0e6f" xlink:to="loc_us-gaap_OperatingLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList_d0766e23-f269-4ab2-b36c-d5b979575de5" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherLiabilitiesNoncurrentAbstract_8a182fe6-5732-43e3-a36b-0ce2ba7a30dc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherLiabilitiesNoncurrentAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_f54855df-6a9b-479b-9284-31a10a297958" xlink:to="loc_us-gaap_OtherLiabilitiesNoncurrentAbstract_8a182fe6-5732-43e3-a36b-0ce2ba7a30dc" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_ContingentLiabilitiesNoncurrent_a238b588-315d-4f69-9929-70b231e3f0f0" xlink:href="lxfr-20250629.xsd#lxfr_ContingentLiabilitiesNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherLiabilitiesNoncurrentAbstract_8a182fe6-5732-43e3-a36b-0ce2ba7a30dc" xlink:to="loc_lxfr_ContingentLiabilitiesNoncurrent_a238b588-315d-4f69-9929-70b231e3f0f0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseLiabilityNoncurrent_3619f7ef-4cf9-47a9-ba31-6e0455b7f4a4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseLiabilityNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherLiabilitiesNoncurrentAbstract_8a182fe6-5732-43e3-a36b-0ce2ba7a30dc" xlink:to="loc_us-gaap_OperatingLeaseLiabilityNoncurrent_3619f7ef-4cf9-47a9-ba31-6e0455b7f4a4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherSundryLiabilitiesNoncurrent_dde68dd4-2965-4cd5-88e0-46947c91c0ec" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherSundryLiabilitiesNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherLiabilitiesNoncurrentAbstract_8a182fe6-5732-43e3-a36b-0ce2ba7a30dc" xlink:to="loc_us-gaap_OtherSundryLiabilitiesNoncurrent_dde68dd4-2965-4cd5-88e0-46947c91c0ec" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherLiabilitiesNoncurrent_09de17e8-7d4c-4e8e-b6db-0cb88bb4cf2e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherLiabilitiesNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherLiabilitiesNoncurrentAbstract_8a182fe6-5732-43e3-a36b-0ce2ba7a30dc" xlink:to="loc_us-gaap_OtherLiabilitiesNoncurrent_09de17e8-7d4c-4e8e-b6db-0cb88bb4cf2e" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList_37d067b2-56fa-414a-8cce-6ee2811b1028" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherLiabilitiesNoncurrentAbstract_8a182fe6-5732-43e3-a36b-0ce2ba7a30dc" xlink:to="loc_us-gaap_OperatingLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList_37d067b2-56fa-414a-8cce-6ee2811b1028" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.luxfer.com/role/GoodwillandotheridentifiableintangibleassetsScheduleofGoodwillDetails" xlink:type="simple" xlink:href="lxfr-20250629.xsd#GoodwillandotheridentifiableintangibleassetsScheduleofGoodwillDetails"/>
  <link:definitionLink xlink:role="http://www.luxfer.com/role/GoodwillandotheridentifiableintangibleassetsScheduleofGoodwillDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillLineItems_761a4d27-1bf8-4069-a9a3-aa310e3a1b17" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GoodwillLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfGoodwillTable_ca00b479-7e68-4a3c-b82e-0c4a077843b5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfGoodwillTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_GoodwillLineItems_761a4d27-1bf8-4069-a9a3-aa310e3a1b17" xlink:to="loc_us-gaap_ScheduleOfGoodwillTable_ca00b479-7e68-4a3c-b82e-0c4a077843b5" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_31fa956b-e9b3-474f-aa70-ae9b0c13369a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfGoodwillTable_ca00b479-7e68-4a3c-b82e-0c4a077843b5" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_31fa956b-e9b3-474f-aa70-ae9b0c13369a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_31fa956b-e9b3-474f-aa70-ae9b0c13369a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_31fa956b-e9b3-474f-aa70-ae9b0c13369a" xlink:to="loc_us-gaap_SegmentDomain_31fa956b-e9b3-474f-aa70-ae9b0c13369a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_6c5ddc06-3641-4287-af16-7a0c54c22ac9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_31fa956b-e9b3-474f-aa70-ae9b0c13369a" xlink:to="loc_us-gaap_SegmentDomain_6c5ddc06-3641-4287-af16-7a0c54c22ac9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_GasCylindersSegmentMember_85ff02f8-f76b-4ce0-9e56-857567fc1d68" xlink:href="lxfr-20250629.xsd#lxfr_GasCylindersSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_6c5ddc06-3641-4287-af16-7a0c54c22ac9" xlink:to="loc_lxfr_GasCylindersSegmentMember_85ff02f8-f76b-4ce0-9e56-857567fc1d68" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_ElektronSegmentMember_db24e909-84ff-4194-827a-63387ab3973d" xlink:href="lxfr-20250629.xsd#lxfr_ElektronSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_6c5ddc06-3641-4287-af16-7a0c54c22ac9" xlink:to="loc_lxfr_ElektronSegmentMember_db24e909-84ff-4194-827a-63387ab3973d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillRollForward_4e8dc344-8e61-475f-9b5e-0a0d47941a07" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GoodwillRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillLineItems_761a4d27-1bf8-4069-a9a3-aa310e3a1b17" xlink:to="loc_us-gaap_GoodwillRollForward_4e8dc344-8e61-475f-9b5e-0a0d47941a07" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_12ee4903-828a-4fd3-bb1c-9681be9d381b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Goodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillRollForward_4e8dc344-8e61-475f-9b5e-0a0d47941a07" xlink:to="loc_us-gaap_Goodwill_12ee4903-828a-4fd3-bb1c-9681be9d381b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillForeignCurrencyTranslationGainLoss_e5183c4c-bfef-4b14-aa9f-31bee8af02b3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GoodwillForeignCurrencyTranslationGainLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillRollForward_4e8dc344-8e61-475f-9b5e-0a0d47941a07" xlink:to="loc_us-gaap_GoodwillForeignCurrencyTranslationGainLoss_e5183c4c-bfef-4b14-aa9f-31bee8af02b3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_dd6ab4e8-7577-4a27-a371-11b52b5b908b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Goodwill"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.luxfer.com/role/GoodwillandotheridentifiableintangibleassetsScheduleofIntangibleAssetsDetails" xlink:type="simple" xlink:href="lxfr-20250629.xsd#GoodwillandotheridentifiableintangibleassetsScheduleofIntangibleAssetsDetails"/>
  <link:definitionLink xlink:role="http://www.luxfer.com/role/GoodwillandotheridentifiableintangibleassetsScheduleofIntangibleAssetsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_d7be1afa-6f6a-4185-8e6f-4d115cf631ca" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_de3454d3-da33-41dc-8a04-92a210a666ab" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_d7be1afa-6f6a-4185-8e6f-4d115cf631ca" xlink:to="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_de3454d3-da33-41dc-8a04-92a210a666ab" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_78f8368d-782d-4e27-8fdb-41e0b3bf8518" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_de3454d3-da33-41dc-8a04-92a210a666ab" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_78f8368d-782d-4e27-8fdb-41e0b3bf8518" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_78f8368d-782d-4e27-8fdb-41e0b3bf8518_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_78f8368d-782d-4e27-8fdb-41e0b3bf8518" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_78f8368d-782d-4e27-8fdb-41e0b3bf8518_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_1c77730a-c525-4c28-90dc-adfa6f08e685" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_78f8368d-782d-4e27-8fdb-41e0b3bf8518" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_1c77730a-c525-4c28-90dc-adfa6f08e685" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CustomerRelationshipsMember_97bb9b86-34cb-454b-9434-4230ed9296ba" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CustomerRelationshipsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_1c77730a-c525-4c28-90dc-adfa6f08e685" xlink:to="loc_us-gaap_CustomerRelationshipsMember_97bb9b86-34cb-454b-9434-4230ed9296ba" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TechnologyBasedIntangibleAssetsMember_e42d062c-0f63-4a30-8927-81d6b54c110c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TechnologyBasedIntangibleAssetsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_1c77730a-c525-4c28-90dc-adfa6f08e685" xlink:to="loc_us-gaap_TechnologyBasedIntangibleAssetsMember_e42d062c-0f63-4a30-8927-81d6b54c110c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsRollForward_19aff600-f072-4da0-9ef6-97c255221359" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_d7be1afa-6f6a-4185-8e6f-4d115cf631ca" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsRollForward_19aff600-f072-4da0-9ef6-97c255221359" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsGross_a510d23c-0f60-4844-bc35-76426859b980" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsRollForward_19aff600-f072-4da0-9ef6-97c255221359" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsGross_a510d23c-0f60-4844-bc35-76426859b980" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsForeignCurrencyTranslationGainLoss_bea2c1f0-5453-4059-a0f6-0a0e8e38ebe4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsForeignCurrencyTranslationGainLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsRollForward_19aff600-f072-4da0-9ef6-97c255221359" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsForeignCurrencyTranslationGainLoss_bea2c1f0-5453-4059-a0f6-0a0e8e38ebe4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsGross_be90dacd-b21c-41b3-910e-fd1e7a7e6b4f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsGross"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentForAmortizationAbstract_a6b1b034-e055-44ab-982f-5739190f52a1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdjustmentForAmortizationAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_d7be1afa-6f6a-4185-8e6f-4d115cf631ca" xlink:to="loc_us-gaap_AdjustmentForAmortizationAbstract_a6b1b034-e055-44ab-982f-5739190f52a1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_ad442a75-f8ed-459d-8fe6-eb16bb761547" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AdjustmentForAmortizationAbstract_a6b1b034-e055-44ab-982f-5739190f52a1" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_ad442a75-f8ed-459d-8fe6-eb16bb761547" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AmortizationOfIntangibleAssets_f2280ad4-cb78-4b37-8828-d285fd1c1f5c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AmortizationOfIntangibleAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AdjustmentForAmortizationAbstract_a6b1b034-e055-44ab-982f-5739190f52a1" xlink:to="loc_us-gaap_AmortizationOfIntangibleAssets_f2280ad4-cb78-4b37-8828-d285fd1c1f5c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_FiniteLivedIntangibleAssetsAccumulatedAmortizationForeignCurrencyTranslationGainLoss_9cc8d531-0e11-4aed-90e7-af77381109df" xlink:href="lxfr-20250629.xsd#lxfr_FiniteLivedIntangibleAssetsAccumulatedAmortizationForeignCurrencyTranslationGainLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AdjustmentForAmortizationAbstract_a6b1b034-e055-44ab-982f-5739190f52a1" xlink:to="loc_lxfr_FiniteLivedIntangibleAssetsAccumulatedAmortizationForeignCurrencyTranslationGainLoss_9cc8d531-0e11-4aed-90e7-af77381109df" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_5ae59d88-4499-4936-8ad1-193146d7256e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsNet_8a3c3d02-9105-40aa-a12e-45542a727e67" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_d7be1afa-6f6a-4185-8e6f-4d115cf631ca" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsNet_8a3c3d02-9105-40aa-a12e-45542a727e67" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.luxfer.com/role/DebtScheduleofDebtOutstandingDetails" xlink:type="simple" xlink:href="lxfr-20250629.xsd#DebtScheduleofDebtOutstandingDetails"/>
  <link:definitionLink xlink:role="http://www.luxfer.com/role/DebtScheduleofDebtOutstandingDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_6681805c-4b89-46c2-b97d-0f7e23268cf4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_920ba064-e39c-43f0-82df-aab27c7c2de7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_6681805c-4b89-46c2-b97d-0f7e23268cf4" xlink:to="loc_us-gaap_DebtInstrumentTable_920ba064-e39c-43f0-82df-aab27c7c2de7" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_55ac3e9c-654a-49a0-b5fb-ddbd4817aa5c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_920ba064-e39c-43f0-82df-aab27c7c2de7" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_55ac3e9c-654a-49a0-b5fb-ddbd4817aa5c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_55ac3e9c-654a-49a0-b5fb-ddbd4817aa5c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_55ac3e9c-654a-49a0-b5fb-ddbd4817aa5c" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_55ac3e9c-654a-49a0-b5fb-ddbd4817aa5c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_146877b4-69ba-4b2b-8158-965b66aeb5fa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_55ac3e9c-654a-49a0-b5fb-ddbd4817aa5c" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_146877b4-69ba-4b2b-8158-965b66aeb5fa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeniorNotesMember_7bddf2f5-2c25-436c-a678-a7182f498f4d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SeniorNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_146877b4-69ba-4b2b-8158-965b66aeb5fa" xlink:to="loc_us-gaap_SeniorNotesMember_7bddf2f5-2c25-436c-a678-a7182f498f4d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_9e8957b6-4e85-4914-876e-6f589e3c74f9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_920ba064-e39c-43f0-82df-aab27c7c2de7" xlink:to="loc_us-gaap_DebtInstrumentAxis_9e8957b6-4e85-4914-876e-6f589e3c74f9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_9e8957b6-4e85-4914-876e-6f589e3c74f9_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_9e8957b6-4e85-4914-876e-6f589e3c74f9" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_9e8957b6-4e85-4914-876e-6f589e3c74f9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_832c86b2-e6ae-4c4a-a175-7155e3ced3d3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_9e8957b6-4e85-4914-876e-6f589e3c74f9" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_832c86b2-e6ae-4c4a-a175-7155e3ced3d3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_LoanNotesDue2026Member_45232efd-dfe5-4398-8bac-39461dc02c93" xlink:href="lxfr-20250629.xsd#lxfr_LoanNotesDue2026Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_832c86b2-e6ae-4c4a-a175-7155e3ced3d3" xlink:to="loc_lxfr_LoanNotesDue2026Member_45232efd-dfe5-4398-8bac-39461dc02c93" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BankOverdraftsMember_272f7f31-857f-4b6b-b366-ab820d1644cb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BankOverdraftsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_832c86b2-e6ae-4c4a-a175-7155e3ced3d3" xlink:to="loc_us-gaap_BankOverdraftsMember_272f7f31-857f-4b6b-b366-ab820d1644cb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_920645e1-cfef-4813-88de-8a28239a3654" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_920ba064-e39c-43f0-82df-aab27c7c2de7" xlink:to="loc_us-gaap_CreditFacilityAxis_920645e1-cfef-4813-88de-8a28239a3654" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_920645e1-cfef-4813-88de-8a28239a3654_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_920645e1-cfef-4813-88de-8a28239a3654" xlink:to="loc_us-gaap_CreditFacilityDomain_920645e1-cfef-4813-88de-8a28239a3654_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_8d97b181-5275-4f06-8b77-3677ac27b833" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_920645e1-cfef-4813-88de-8a28239a3654" xlink:to="loc_us-gaap_CreditFacilityDomain_8d97b181-5275-4f06-8b77-3677ac27b833" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_54046660-abf0-4669-9e92-06d20c97ef2c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevolvingCreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_8d97b181-5275-4f06-8b77-3677ac27b833" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_54046660-abf0-4669-9e92-06d20c97ef2c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_1b011032-7330-4ec5-bdf8-4a56e5ba400b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_6681805c-4b89-46c2-b97d-0f7e23268cf4" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_1b011032-7330-4ec5-bdf8-4a56e5ba400b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentCarryingAmount_e5512cfa-c94c-4cb5-83c3-0c6c060af73f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentCarryingAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_6681805c-4b89-46c2-b97d-0f7e23268cf4" xlink:to="loc_us-gaap_DebtInstrumentCarryingAmount_e5512cfa-c94c-4cb5-83c3-0c6c060af73f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredFinanceCostsNet_79b5d37e-06da-436e-9962-68a430c15d30" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DeferredFinanceCostsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_6681805c-4b89-46c2-b97d-0f7e23268cf4" xlink:to="loc_us-gaap_DeferredFinanceCostsNet_79b5d37e-06da-436e-9962-68a430c15d30" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebt_7af48199-dc85-455f-8733-739779864c14" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_6681805c-4b89-46c2-b97d-0f7e23268cf4" xlink:to="loc_us-gaap_LongTermDebt_7af48199-dc85-455f-8733-739779864c14" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtCurrent_04eb7995-e301-42b9-98dd-d1a190d07c00" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebtCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_6681805c-4b89-46c2-b97d-0f7e23268cf4" xlink:to="loc_us-gaap_LongTermDebtCurrent_04eb7995-e301-42b9-98dd-d1a190d07c00" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtNoncurrent_c8fc8840-7275-49c4-a114-956789cdbd7a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebtNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_6681805c-4b89-46c2-b97d-0f7e23268cf4" xlink:to="loc_us-gaap_LongTermDebtNoncurrent_c8fc8840-7275-49c4-a114-956789cdbd7a" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.luxfer.com/role/DebtAdditionalInformationDetails" xlink:type="simple" xlink:href="lxfr-20250629.xsd#DebtAdditionalInformationDetails"/>
  <link:definitionLink xlink:role="http://www.luxfer.com/role/DebtAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_5e9a7544-1cdb-4946-b9eb-4e4f3b1bb502" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_5034caeb-5fbb-4027-8a06-5424131907fd" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_5e9a7544-1cdb-4946-b9eb-4e4f3b1bb502" xlink:to="loc_us-gaap_DebtInstrumentTable_5034caeb-5fbb-4027-8a06-5424131907fd" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_96e86986-c8a6-4a58-991b-ed0e2eb5079a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_5034caeb-5fbb-4027-8a06-5424131907fd" xlink:to="loc_us-gaap_CreditFacilityAxis_96e86986-c8a6-4a58-991b-ed0e2eb5079a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_96e86986-c8a6-4a58-991b-ed0e2eb5079a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_96e86986-c8a6-4a58-991b-ed0e2eb5079a" xlink:to="loc_us-gaap_CreditFacilityDomain_96e86986-c8a6-4a58-991b-ed0e2eb5079a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_2c672a70-5019-4a01-9d0f-f87cc3f08f4a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_96e86986-c8a6-4a58-991b-ed0e2eb5079a" xlink:to="loc_us-gaap_CreditFacilityDomain_2c672a70-5019-4a01-9d0f-f87cc3f08f4a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_4359ad23-feef-49b6-8550-c86e37583a02" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevolvingCreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_2c672a70-5019-4a01-9d0f-f87cc3f08f4a" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_4359ad23-feef-49b6-8550-c86e37583a02" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtWeightedAverageInterestRate_e6cbc5af-ef0e-4f7b-a76c-9a23d21eeffe" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtWeightedAverageInterestRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_5e9a7544-1cdb-4946-b9eb-4e4f3b1bb502" xlink:to="loc_us-gaap_DebtWeightedAverageInterestRate_e6cbc5af-ef0e-4f7b-a76c-9a23d21eeffe" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromRepaymentsOfLongTermDebtAndCapitalSecurities_45495029-a532-4ac3-b0a2-840cce2349d5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromRepaymentsOfLongTermDebtAndCapitalSecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_5e9a7544-1cdb-4946-b9eb-4e4f3b1bb502" xlink:to="loc_us-gaap_ProceedsFromRepaymentsOfLongTermDebtAndCapitalSecurities_45495029-a532-4ac3-b0a2-840cce2349d5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentCarryingAmount_d1adc3e9-1f47-468d-b02a-76c52773489c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentCarryingAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_5e9a7544-1cdb-4946-b9eb-4e4f3b1bb502" xlink:to="loc_us-gaap_DebtInstrumentCarryingAmount_d1adc3e9-1f47-468d-b02a-76c52773489c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity_0127ede6-99cb-405d-893a-acd0c58a5374" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_5e9a7544-1cdb-4946-b9eb-4e4f3b1bb502" xlink:to="loc_us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity_0127ede6-99cb-405d-893a-acd0c58a5374" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.luxfer.com/role/DiscontinuedOperationsResultsofDiscontinuedOperationsDetails" xlink:type="simple" xlink:href="lxfr-20250629.xsd#DiscontinuedOperationsResultsofDiscontinuedOperationsDetails"/>
  <link:definitionLink xlink:role="http://www.luxfer.com/role/DiscontinuedOperationsResultsofDiscontinuedOperationsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_8d2cf336-545f-40dd-a5c1-1d1ff5a8b2fe" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_8520476f-93ab-4662-9cb5-0d01834a88ff" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_8d2cf336-545f-40dd-a5c1-1d1ff5a8b2fe" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_8520476f-93ab-4662-9cb5-0d01834a88ff" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationAxis_c17a3fa7-27ff-47cd-acaf-29c6803299cb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupClassificationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_8520476f-93ab-4662-9cb5-0d01834a88ff" xlink:to="loc_us-gaap_DisposalGroupClassificationAxis_c17a3fa7-27ff-47cd-acaf-29c6803299cb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_c17a3fa7-27ff-47cd-acaf-29c6803299cb_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_c17a3fa7-27ff-47cd-acaf-29c6803299cb" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_c17a3fa7-27ff-47cd-acaf-29c6803299cb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_24c95320-b815-496b-aa50-524e45338eda" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_c17a3fa7-27ff-47cd-acaf-29c6803299cb" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_24c95320-b815-496b-aa50-524e45338eda" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DiscontinuedOperationsHeldforsaleMember_f82c9d4d-4034-474f-b57a-69e16deaacbb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DiscontinuedOperationsHeldforsaleMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupClassificationDomain_24c95320-b815-496b-aa50-524e45338eda" xlink:to="loc_us-gaap_DiscontinuedOperationsHeldforsaleMember_f82c9d4d-4034-474f-b57a-69e16deaacbb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_6afe5f6d-072d-4bf9-b977-e3965c0e83df" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_8520476f-93ab-4662-9cb5-0d01834a88ff" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_6afe5f6d-072d-4bf9-b977-e3965c0e83df" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_6afe5f6d-072d-4bf9-b977-e3965c0e83df_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_6afe5f6d-072d-4bf9-b977-e3965c0e83df" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_6afe5f6d-072d-4bf9-b977-e3965c0e83df_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_756fc04c-9a5a-44e5-a522-38f75b53b6db" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_6afe5f6d-072d-4bf9-b977-e3965c0e83df" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_756fc04c-9a5a-44e5-a522-38f75b53b6db" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_SuperformAluminumSuperplasticMember_1a53bad6-2c47-4ceb-b481-25b97909d9cc" xlink:href="lxfr-20250629.xsd#lxfr_SuperformAluminumSuperplasticMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_756fc04c-9a5a-44e5-a522-38f75b53b6db" xlink:to="loc_lxfr_SuperformAluminumSuperplasticMember_1a53bad6-2c47-4ceb-b481-25b97909d9cc" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationRevenue_24f9f402-7486-4348-84f9-f8539b8d4cdc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationRevenue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_8d2cf336-545f-40dd-a5c1-1d1ff5a8b2fe" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationRevenue_24f9f402-7486-4348-84f9-f8539b8d4cdc" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationCostsOfGoodsSold_f0fb9531-d3ce-4bca-9185-8751f8ff4e9f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationCostsOfGoodsSold"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_8d2cf336-545f-40dd-a5c1-1d1ff5a8b2fe" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationCostsOfGoodsSold_f0fb9531-d3ce-4bca-9185-8751f8ff4e9f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationGrossProfitLoss_4912c2b3-ef4b-4961-8122-8d2419cb103d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationGrossProfitLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_8d2cf336-545f-40dd-a5c1-1d1ff5a8b2fe" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationGrossProfitLoss_4912c2b3-ef4b-4961-8122-8d2419cb103d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationGeneralAndAdministrativeExpense_3f26ced7-a133-4481-9a92-64d292724b56" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationGeneralAndAdministrativeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_8d2cf336-545f-40dd-a5c1-1d1ff5a8b2fe" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationGeneralAndAdministrativeExpense_3f26ced7-a133-4481-9a92-64d292724b56" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_DisposalGroupIncludingDiscontinuedOperationRestructuringCreditCharge_a983bae4-d490-42c1-bd74-7e15dbe32a3a" xlink:href="lxfr-20250629.xsd#lxfr_DisposalGroupIncludingDiscontinuedOperationRestructuringCreditCharge"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_8d2cf336-545f-40dd-a5c1-1d1ff5a8b2fe" xlink:to="loc_lxfr_DisposalGroupIncludingDiscontinuedOperationRestructuringCreditCharge_a983bae4-d490-42c1-bd74-7e15dbe32a3a" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DiscontinuedOperationProvisionForLossGainOnDisposalBeforeIncomeTax_15ba0708-1229-402a-8aa3-5f87d996f459" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DiscontinuedOperationProvisionForLossGainOnDisposalBeforeIncomeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_8d2cf336-545f-40dd-a5c1-1d1ff5a8b2fe" xlink:to="loc_us-gaap_DiscontinuedOperationProvisionForLossGainOnDisposalBeforeIncomeTax_15ba0708-1229-402a-8aa3-5f87d996f459" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationOperatingIncomeLoss_b6c75253-5935-43fb-9029-85edeca30060" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationOperatingIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_8d2cf336-545f-40dd-a5c1-1d1ff5a8b2fe" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationOperatingIncomeLoss_b6c75253-5935-43fb-9029-85edeca30060" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DiscontinuedOperationTaxEffectOfIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriod_0617efba-a7bc-4371-9b34-eb822a5a36fa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DiscontinuedOperationTaxEffectOfIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_8d2cf336-545f-40dd-a5c1-1d1ff5a8b2fe" xlink:to="loc_us-gaap_DiscontinuedOperationTaxEffectOfIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriod_0617efba-a7bc-4371-9b34-eb822a5a36fa" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodNetOfTax_f9384a0f-7f39-49ac-9c2c-3d798315f95f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_8d2cf336-545f-40dd-a5c1-1d1ff5a8b2fe" xlink:to="loc_us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodNetOfTax_f9384a0f-7f39-49ac-9c2c-3d798315f95f" xlink:type="arc" order="8"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.luxfer.com/role/DiscontinuedOperationsAssetsandLiabilitiesDetails" xlink:type="simple" xlink:href="lxfr-20250629.xsd#DiscontinuedOperationsAssetsandLiabilitiesDetails"/>
  <link:definitionLink xlink:role="http://www.luxfer.com/role/DiscontinuedOperationsAssetsandLiabilitiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_53a7f1e4-85f1-47cf-9d9b-706775ea8146" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_5ba36e05-e1f0-47ed-a77d-f04ce95bd11f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_53a7f1e4-85f1-47cf-9d9b-706775ea8146" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_5ba36e05-e1f0-47ed-a77d-f04ce95bd11f" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationAxis_cb59efc0-9021-4834-944f-d9fb94b7d431" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupClassificationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_5ba36e05-e1f0-47ed-a77d-f04ce95bd11f" xlink:to="loc_us-gaap_DisposalGroupClassificationAxis_cb59efc0-9021-4834-944f-d9fb94b7d431" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_cb59efc0-9021-4834-944f-d9fb94b7d431_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_cb59efc0-9021-4834-944f-d9fb94b7d431" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_cb59efc0-9021-4834-944f-d9fb94b7d431_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_91b23cb5-417e-4399-9efc-7b5616b6c9f3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_cb59efc0-9021-4834-944f-d9fb94b7d431" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_91b23cb5-417e-4399-9efc-7b5616b6c9f3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDiscontinuedOperationsMember_d4734bf7-93af-4b12-b433-cff92a5c205e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDiscontinuedOperationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupClassificationDomain_91b23cb5-417e-4399-9efc-7b5616b6c9f3" xlink:to="loc_us-gaap_SegmentDiscontinuedOperationsMember_d4734bf7-93af-4b12-b433-cff92a5c205e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_1b2a08d3-abd3-48de-b5d8-e538c7df706d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_5ba36e05-e1f0-47ed-a77d-f04ce95bd11f" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_1b2a08d3-abd3-48de-b5d8-e538c7df706d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_1b2a08d3-abd3-48de-b5d8-e538c7df706d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_1b2a08d3-abd3-48de-b5d8-e538c7df706d" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_1b2a08d3-abd3-48de-b5d8-e538c7df706d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_2a6c0dfe-38e9-4e68-9c99-24ed8d657e49" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_1b2a08d3-abd3-48de-b5d8-e538c7df706d" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_2a6c0dfe-38e9-4e68-9c99-24ed8d657e49" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_SuperformU.SBusinessMember_d6e37e8f-7887-4624-b4ea-d57c7335a7a9" xlink:href="lxfr-20250629.xsd#lxfr_SuperformU.SBusinessMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_2a6c0dfe-38e9-4e68-9c99-24ed8d657e49" xlink:to="loc_lxfr_SuperformU.SBusinessMember_d6e37e8f-7887-4624-b4ea-d57c7335a7a9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationAbstract_42a7e561-8b06-4077-b653-933a6d1790ab" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_53a7f1e4-85f1-47cf-9d9b-706775ea8146" xlink:to="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationAbstract_42a7e561-8b06-4077-b653-933a6d1790ab" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationInventoryCurrent_dae21972-f366-497d-ad49-e3f775258de6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationInventoryCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationAbstract_42a7e561-8b06-4077-b653-933a6d1790ab" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationInventoryCurrent_dae21972-f366-497d-ad49-e3f775258de6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationPrepaidAndOtherAssets_1bd2d9b0-bf00-4001-8792-6cc76c17c44b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationPrepaidAndOtherAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationAbstract_42a7e561-8b06-4077-b653-933a6d1790ab" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationPrepaidAndOtherAssets_1bd2d9b0-bf00-4001-8792-6cc76c17c44b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsNotesAndLoansReceivableNet_e5a11f82-fec4-4a48-a556-34288d6ce9a5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsNotesAndLoansReceivableNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationAbstract_42a7e561-8b06-4077-b653-933a6d1790ab" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsNotesAndLoansReceivableNet_e5a11f82-fec4-4a48-a556-34288d6ce9a5" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationCurrent_65fff372-db08-4fde-b112-fbac09502815" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationAbstract_42a7e561-8b06-4077-b653-933a6d1790ab" xlink:to="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationCurrent_65fff372-db08-4fde-b112-fbac09502815" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_DisposalGroupIncludingDiscontinuedOperationOperatingLeaseRightOfUseAsset_2d58bc5a-295a-494c-aaab-d51fccb6f323" xlink:href="lxfr-20250629.xsd#lxfr_DisposalGroupIncludingDiscontinuedOperationOperatingLeaseRightOfUseAsset"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationAbstract_42a7e561-8b06-4077-b653-933a6d1790ab" xlink:to="loc_lxfr_DisposalGroupIncludingDiscontinuedOperationOperatingLeaseRightOfUseAsset_2d58bc5a-295a-494c-aaab-d51fccb6f323" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationAssetsNoncurrent_f273a3f5-c9e7-4e3a-8eef-41019d56e29d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationAssetsNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationAbstract_42a7e561-8b06-4077-b653-933a6d1790ab" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationAssetsNoncurrent_f273a3f5-c9e7-4e3a-8eef-41019d56e29d" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperation_df623d83-c185-4c90-8116-f0ec1e5ed6e9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationAbstract_42a7e561-8b06-4077-b653-933a6d1790ab" xlink:to="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperation_df623d83-c185-4c90-8116-f0ec1e5ed6e9" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationAbstract_8fe901aa-56fc-431f-968f-0bb7de3149a1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_53a7f1e4-85f1-47cf-9d9b-706775ea8146" xlink:to="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationAbstract_8fe901aa-56fc-431f-968f-0bb7de3149a1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsPayableCurrent_17b5a734-79f6-4a1c-b9a5-0e37abb9188d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsPayableCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationAbstract_8fe901aa-56fc-431f-968f-0bb7de3149a1" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsPayableCurrent_17b5a734-79f6-4a1c-b9a5-0e37abb9188d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationAccruedLiabilities_9ec7b656-72fe-4e5e-b85e-f0e49a992111" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationAccruedLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationAbstract_8fe901aa-56fc-431f-968f-0bb7de3149a1" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationAccruedLiabilities_9ec7b656-72fe-4e5e-b85e-f0e49a992111" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherCurrentLiabilities_098b8ff4-4922-4b49-b647-7cb8297cb84b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherCurrentLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationAbstract_8fe901aa-56fc-431f-968f-0bb7de3149a1" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherCurrentLiabilities_098b8ff4-4922-4b49-b647-7cb8297cb84b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationCurrent_05babd6e-56e3-4c06-8cde-7a301300091a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationAbstract_8fe901aa-56fc-431f-968f-0bb7de3149a1" xlink:to="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationCurrent_05babd6e-56e3-4c06-8cde-7a301300091a" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperation_932c6214-6298-4d75-9bc6-3d822a355a9f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationAbstract_8fe901aa-56fc-431f-968f-0bb7de3149a1" xlink:to="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperation_932c6214-6298-4d75-9bc6-3d822a355a9f" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.luxfer.com/role/DiscontinuedOperationsAdditionalInformationDetails" xlink:type="simple" xlink:href="lxfr-20250629.xsd#DiscontinuedOperationsAdditionalInformationDetails"/>
  <link:definitionLink xlink:role="http://www.luxfer.com/role/DiscontinuedOperationsAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_a85d5da5-7a60-47c3-8084-e6e61d5c6f4d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_10559b3d-7fd1-4cd8-a1d8-a9eef72dc6ee" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_a85d5da5-7a60-47c3-8084-e6e61d5c6f4d" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_10559b3d-7fd1-4cd8-a1d8-a9eef72dc6ee" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_322bf52c-c10f-4e6b-8c42-769110cecc53" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_10559b3d-7fd1-4cd8-a1d8-a9eef72dc6ee" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_322bf52c-c10f-4e6b-8c42-769110cecc53" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_322bf52c-c10f-4e6b-8c42-769110cecc53_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_322bf52c-c10f-4e6b-8c42-769110cecc53" xlink:to="loc_us-gaap_SegmentDomain_322bf52c-c10f-4e6b-8c42-769110cecc53_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_e8848901-fe43-4fda-96d8-d19819a72edf" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_322bf52c-c10f-4e6b-8c42-769110cecc53" xlink:to="loc_us-gaap_SegmentDomain_e8848901-fe43-4fda-96d8-d19819a72edf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_SuperformU.SBusinessMember_14fe8d82-2727-4f14-a540-9f3ec9a0720f" xlink:href="lxfr-20250629.xsd#lxfr_SuperformU.SBusinessMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_e8848901-fe43-4fda-96d8-d19819a72edf" xlink:to="loc_lxfr_SuperformU.SBusinessMember_14fe8d82-2727-4f14-a540-9f3ec9a0720f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByAssetClassAxis_7484eb6d-7a08-486e-83e0-ec75f9f782c1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueByAssetClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_10559b3d-7fd1-4cd8-a1d8-a9eef72dc6ee" xlink:to="loc_us-gaap_FairValueByAssetClassAxis_7484eb6d-7a08-486e-83e0-ec75f9f782c1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_7484eb6d-7a08-486e-83e0-ec75f9f782c1_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByAssetClassAxis_7484eb6d-7a08-486e-83e0-ec75f9f782c1" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_7484eb6d-7a08-486e-83e0-ec75f9f782c1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_cf8a4600-1b04-462a-afe9-534a225e4d2a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByAssetClassAxis_7484eb6d-7a08-486e-83e0-ec75f9f782c1" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_cf8a4600-1b04-462a-afe9-534a225e4d2a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoriesMember_b75f662a-6d91-486d-97f0-f24bee822b81" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InventoriesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_cf8a4600-1b04-462a-afe9-534a225e4d2a" xlink:to="loc_us-gaap_InventoriesMember_b75f662a-6d91-486d-97f0-f24bee822b81" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentMember_5797b65c-65df-4570-ac91-d86cc27b70a2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_cf8a4600-1b04-462a-afe9-534a225e4d2a" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentMember_5797b65c-65df-4570-ac91-d86cc27b70a2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_OperatingLeaseRightOfUseAssetsMember_7e08567e-68df-4b08-ba6c-a1b359b70418" xlink:href="lxfr-20250629.xsd#lxfr_OperatingLeaseRightOfUseAssetsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_cf8a4600-1b04-462a-afe9-534a225e4d2a" xlink:to="loc_lxfr_OperatingLeaseRightOfUseAssetsMember_7e08567e-68df-4b08-ba6c-a1b359b70418" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations_22d75197-2d94-461e-b27c-a837c8981f49" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_a85d5da5-7a60-47c3-8084-e6e61d5c6f4d" xlink:to="loc_us-gaap_CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations_22d75197-2d94-461e-b27c-a837c8981f49" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationAndAmortizationDiscontinuedOperations_46ea65d7-1810-4f01-ae20-cb1a886dc3c3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DepreciationAndAmortizationDiscontinuedOperations"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_a85d5da5-7a60-47c3-8084-e6e61d5c6f4d" xlink:to="loc_us-gaap_DepreciationAndAmortizationDiscontinuedOperations_46ea65d7-1810-4f01-ae20-cb1a886dc3c3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DiscontinuedOperationProvisionForLossGainOnDisposalBeforeIncomeTax_dee1a08e-8725-4b0d-b783-d088234e7b11" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DiscontinuedOperationProvisionForLossGainOnDisposalBeforeIncomeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_a85d5da5-7a60-47c3-8084-e6e61d5c6f4d" xlink:to="loc_us-gaap_DiscontinuedOperationProvisionForLossGainOnDisposalBeforeIncomeTax_dee1a08e-8725-4b0d-b783-d088234e7b11" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.luxfer.com/role/HeldforsaleassetsandliabilitiesScheduleofCurrentHeldforSaleAssetsandLiabilitiesDetails" xlink:type="simple" xlink:href="lxfr-20250629.xsd#HeldforsaleassetsandliabilitiesScheduleofCurrentHeldforSaleAssetsandLiabilitiesDetails"/>
  <link:definitionLink xlink:role="http://www.luxfer.com/role/HeldforsaleassetsandliabilitiesScheduleofCurrentHeldforSaleAssetsandLiabilitiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_0a4c5ec5-6061-4035-8044-417c63caf73a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_8acfc3b1-deb6-4b28-8855-2cace5767ea6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_0a4c5ec5-6061-4035-8044-417c63caf73a" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_8acfc3b1-deb6-4b28-8855-2cace5767ea6" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationAxis_19f461ca-7cdc-4835-856d-3d92b5b00475" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupClassificationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_8acfc3b1-deb6-4b28-8855-2cace5767ea6" xlink:to="loc_us-gaap_DisposalGroupClassificationAxis_19f461ca-7cdc-4835-856d-3d92b5b00475" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_19f461ca-7cdc-4835-856d-3d92b5b00475_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_19f461ca-7cdc-4835-856d-3d92b5b00475" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_19f461ca-7cdc-4835-856d-3d92b5b00475_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_7d49b227-c6b9-4a84-80f0-ea7c90868fec" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_19f461ca-7cdc-4835-856d-3d92b5b00475" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_7d49b227-c6b9-4a84-80f0-ea7c90868fec" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupHeldforsaleNotDiscontinuedOperationsMember_0720a595-083e-4f65-87b5-3e413dec1f59" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupHeldforsaleNotDiscontinuedOperationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupClassificationDomain_7d49b227-c6b9-4a84-80f0-ea7c90868fec" xlink:to="loc_us-gaap_DisposalGroupHeldforsaleNotDiscontinuedOperationsMember_0720a595-083e-4f65-87b5-3e413dec1f59" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_813a3418-54e8-46d0-ac13-cb410f52ac4b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_8acfc3b1-deb6-4b28-8855-2cace5767ea6" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_813a3418-54e8-46d0-ac13-cb410f52ac4b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_813a3418-54e8-46d0-ac13-cb410f52ac4b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_813a3418-54e8-46d0-ac13-cb410f52ac4b" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_813a3418-54e8-46d0-ac13-cb410f52ac4b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_aa609de0-d5a7-4a6d-93f1-368c62c7305b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_813a3418-54e8-46d0-ac13-cb410f52ac4b" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_aa609de0-d5a7-4a6d-93f1-368c62c7305b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_GraphicArtsMember_3fe18895-4520-4f4e-b410-e988d3e19833" xlink:href="lxfr-20250629.xsd#lxfr_GraphicArtsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_aa609de0-d5a7-4a6d-93f1-368c62c7305b" xlink:to="loc_lxfr_GraphicArtsMember_3fe18895-4520-4f4e-b410-e988d3e19833" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationAbstract_e684b97f-f7bd-4544-aed3-963f511709e8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_0a4c5ec5-6061-4035-8044-417c63caf73a" xlink:to="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationAbstract_e684b97f-f7bd-4544-aed3-963f511709e8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationInventoryCurrent_1c8ba7f1-6c2a-4e11-b3e4-7828877db6f9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationInventoryCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationAbstract_e684b97f-f7bd-4544-aed3-963f511709e8" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationInventoryCurrent_1c8ba7f1-6c2a-4e11-b3e4-7828877db6f9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationPrepaidAndOtherAssets_de6d851b-2403-4333-b6e6-dda0ae4be5af" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationPrepaidAndOtherAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationAbstract_e684b97f-f7bd-4544-aed3-963f511709e8" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationPrepaidAndOtherAssets_de6d851b-2403-4333-b6e6-dda0ae4be5af" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsNotesAndLoansReceivableNet_90290433-83ef-4c2e-a9a4-26972faa0a09" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsNotesAndLoansReceivableNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationAbstract_e684b97f-f7bd-4544-aed3-963f511709e8" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsNotesAndLoansReceivableNet_90290433-83ef-4c2e-a9a4-26972faa0a09" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationCurrent_46132b1e-48a3-4865-aadf-5c4ccc669c07" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationAbstract_e684b97f-f7bd-4544-aed3-963f511709e8" xlink:to="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationCurrent_46132b1e-48a3-4865-aadf-5c4ccc669c07" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipmentNoncurrent_920dec8e-6c65-493a-aee2-6d353fc63231" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipmentNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationAbstract_e684b97f-f7bd-4544-aed3-963f511709e8" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipmentNoncurrent_920dec8e-6c65-493a-aee2-6d353fc63231" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_DisposalGroupIncludingDiscontinuedOperationOperatingLeaseRightOfUseAsset_7e1acf5b-d004-407d-bb31-2e9bafa22c8f" xlink:href="lxfr-20250629.xsd#lxfr_DisposalGroupIncludingDiscontinuedOperationOperatingLeaseRightOfUseAsset"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationAbstract_e684b97f-f7bd-4544-aed3-963f511709e8" xlink:to="loc_lxfr_DisposalGroupIncludingDiscontinuedOperationOperatingLeaseRightOfUseAsset_7e1acf5b-d004-407d-bb31-2e9bafa22c8f" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationAssetsNoncurrent_54642cd3-00b7-48fd-a569-549aa46c46d5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationAssetsNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationAbstract_e684b97f-f7bd-4544-aed3-963f511709e8" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationAssetsNoncurrent_54642cd3-00b7-48fd-a569-549aa46c46d5" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperation_f3c890bd-ea66-4530-9ddf-9171e1f0ece2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationAbstract_e684b97f-f7bd-4544-aed3-963f511709e8" xlink:to="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperation_f3c890bd-ea66-4530-9ddf-9171e1f0ece2" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationAbstract_98f2d02a-69d3-40fa-a119-0f2825786a04" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_0a4c5ec5-6061-4035-8044-417c63caf73a" xlink:to="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationAbstract_98f2d02a-69d3-40fa-a119-0f2825786a04" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsPayableCurrent_8b1e4bfd-45a0-4de1-b1e4-bf9f0d18ea23" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsPayableCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationAbstract_98f2d02a-69d3-40fa-a119-0f2825786a04" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsPayableCurrent_8b1e4bfd-45a0-4de1-b1e4-bf9f0d18ea23" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationAccruedLiabilities_a33a6a18-2103-4932-b54c-78982516e716" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationAccruedLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationAbstract_98f2d02a-69d3-40fa-a119-0f2825786a04" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationAccruedLiabilities_a33a6a18-2103-4932-b54c-78982516e716" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherCurrentLiabilities_45bb1ebe-8e9b-4d09-9022-77bb8e4a3ea8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherCurrentLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationAbstract_98f2d02a-69d3-40fa-a119-0f2825786a04" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherCurrentLiabilities_45bb1ebe-8e9b-4d09-9022-77bb8e4a3ea8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationCurrent_a47a41bf-88c1-4273-a3c7-f10375b972c6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationAbstract_98f2d02a-69d3-40fa-a119-0f2825786a04" xlink:to="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationCurrent_a47a41bf-88c1-4273-a3c7-f10375b972c6" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperation_c71fa4a7-9061-466a-a134-185463599357" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationAbstract_98f2d02a-69d3-40fa-a119-0f2825786a04" xlink:to="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperation_c71fa4a7-9061-466a-a134-185463599357" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.luxfer.com/role/HeldforsaleassetsandliabilitiesAdditionalinformationDetails" xlink:type="simple" xlink:href="lxfr-20250629.xsd#HeldforsaleassetsandliabilitiesAdditionalinformationDetails"/>
  <link:definitionLink xlink:role="http://www.luxfer.com/role/HeldforsaleassetsandliabilitiesAdditionalinformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_a4e8d457-477e-47b5-aab4-237b3f28b482" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_5cfa9534-f5e5-4d0b-8a30-2b29f88b2f52" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_a4e8d457-477e-47b5-aab4-237b3f28b482" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_5cfa9534-f5e5-4d0b-8a30-2b29f88b2f52" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_8d6fe99d-93e4-439c-a902-75f109153198" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_5cfa9534-f5e5-4d0b-8a30-2b29f88b2f52" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_8d6fe99d-93e4-439c-a902-75f109153198" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_8d6fe99d-93e4-439c-a902-75f109153198_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_8d6fe99d-93e4-439c-a902-75f109153198" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_8d6fe99d-93e4-439c-a902-75f109153198_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_d5d31cee-89d1-4435-b64e-6eea59607134" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_8d6fe99d-93e4-439c-a902-75f109153198" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_d5d31cee-89d1-4435-b64e-6eea59607134" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_GraphicArtsMember_cd375aad-33f3-49fc-aff1-70318dbf89dd" xlink:href="lxfr-20250629.xsd#lxfr_GraphicArtsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_d5d31cee-89d1-4435-b64e-6eea59607134" xlink:to="loc_lxfr_GraphicArtsMember_cd375aad-33f3-49fc-aff1-70318dbf89dd" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationAxis_e6d7747c-6f3c-4bda-912b-7b3424fb9335" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupClassificationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_5cfa9534-f5e5-4d0b-8a30-2b29f88b2f52" xlink:to="loc_us-gaap_DisposalGroupClassificationAxis_e6d7747c-6f3c-4bda-912b-7b3424fb9335" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_e6d7747c-6f3c-4bda-912b-7b3424fb9335_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_e6d7747c-6f3c-4bda-912b-7b3424fb9335" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_e6d7747c-6f3c-4bda-912b-7b3424fb9335_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_6c87b394-5555-4b6d-a80e-83fb74c1a02e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_e6d7747c-6f3c-4bda-912b-7b3424fb9335" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_6c87b394-5555-4b6d-a80e-83fb74c1a02e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupHeldforsaleNotDiscontinuedOperationsMember_65be9590-d4bd-4d6d-bf3f-8f5dc9f74133" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupHeldforsaleNotDiscontinuedOperationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupClassificationDomain_6c87b394-5555-4b6d-a80e-83fb74c1a02e" xlink:to="loc_us-gaap_DisposalGroupHeldforsaleNotDiscontinuedOperationsMember_65be9590-d4bd-4d6d-bf3f-8f5dc9f74133" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupNotDiscontinuedOperationLossGainOnWriteDown_e20f06d6-42e0-4a5f-a83e-f4d42eca4d35" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisposalGroupNotDiscontinuedOperationLossGainOnWriteDown"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_a4e8d457-477e-47b5-aab4-237b3f28b482" xlink:to="loc_us-gaap_DisposalGroupNotDiscontinuedOperationLossGainOnWriteDown_e20f06d6-42e0-4a5f-a83e-f4d42eca4d35" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringSettlementAndImpairmentProvisions_5f2ac861-76e2-4175-93af-b4e14d505700" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestructuringSettlementAndImpairmentProvisions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_a4e8d457-477e-47b5-aab4-237b3f28b482" xlink:to="loc_us-gaap_RestructuringSettlementAndImpairmentProvisions_5f2ac861-76e2-4175-93af-b4e14d505700" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.luxfer.com/role/SharePlansAdditionalInformationDetails" xlink:type="simple" xlink:href="lxfr-20250629.xsd#SharePlansAdditionalInformationDetails"/>
  <link:definitionLink xlink:role="http://www.luxfer.com/role/SharePlansAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_da33ecc1-a945-45c8-8b86-291712f71e4f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_7aca93c9-f806-4dc1-9eb7-461a4678a22c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_da33ecc1-a945-45c8-8b86-291712f71e4f" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_7aca93c9-f806-4dc1-9eb7-461a4678a22c" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameAxis_f9b221d0-aa39-4328-993c-3b46c5e4474d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_7aca93c9-f806-4dc1-9eb7-461a4678a22c" xlink:to="loc_us-gaap_PlanNameAxis_f9b221d0-aa39-4328-993c-3b46c5e4474d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_f9b221d0-aa39-4328-993c-3b46c5e4474d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PlanNameAxis_f9b221d0-aa39-4328-993c-3b46c5e4474d" xlink:to="loc_us-gaap_PlanNameDomain_f9b221d0-aa39-4328-993c-3b46c5e4474d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_418500a6-1166-4ebe-a1ff-8cce33b5fde2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PlanNameAxis_f9b221d0-aa39-4328-993c-3b46c5e4474d" xlink:to="loc_us-gaap_PlanNameDomain_418500a6-1166-4ebe-a1ff-8cce33b5fde2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_LuxferHoldingsPLCLongTermUmbrellaIncentivePlanMember_de03a86d-ab76-4718-8f08-bf168c5d3a8f" xlink:href="lxfr-20250629.xsd#lxfr_LuxferHoldingsPLCLongTermUmbrellaIncentivePlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PlanNameDomain_418500a6-1166-4ebe-a1ff-8cce33b5fde2" xlink:to="loc_lxfr_LuxferHoldingsPLCLongTermUmbrellaIncentivePlanMember_de03a86d-ab76-4718-8f08-bf168c5d3a8f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_LuxferHoldingsPLCNonExecutiveDirectorsEquityIncentivePlanMember_cbacf081-0e0f-4e72-9f69-981a8d133a72" xlink:href="lxfr-20250629.xsd#lxfr_LuxferHoldingsPLCNonExecutiveDirectorsEquityIncentivePlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PlanNameDomain_418500a6-1166-4ebe-a1ff-8cce33b5fde2" xlink:to="loc_lxfr_LuxferHoldingsPLCNonExecutiveDirectorsEquityIncentivePlanMember_cbacf081-0e0f-4e72-9f69-981a8d133a72" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_077bd88e-16d5-4052-bd83-fa6a33b67bc1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_da33ecc1-a945-45c8-8b86-291712f71e4f" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_077bd88e-16d5-4052-bd83-fa6a33b67bc1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_c35c39e1-73c5-482d-96d8-0946788192fe" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_da33ecc1-a945-45c8-8b86-291712f71e4f" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_c35c39e1-73c5-482d-96d8-0946788192fe" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.luxfer.com/role/SharePlansShareOptionsFairValueAssumptionsDetails" xlink:type="simple" xlink:href="lxfr-20250629.xsd#SharePlansShareOptionsFairValueAssumptionsDetails"/>
  <link:definitionLink xlink:role="http://www.luxfer.com/role/SharePlansShareOptionsFairValueAssumptionsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7fe85411-f3b1-452b-a1fd-783915d06fc1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_86f630f4-6706-4202-bee9-9b70bffb6c37" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7fe85411-f3b1-452b-a1fd-783915d06fc1" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_86f630f4-6706-4202-bee9-9b70bffb6c37" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_4b4b6e92-340a-4102-b4d4-99d96d5b8e98" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_86f630f4-6706-4202-bee9-9b70bffb6c37" xlink:to="loc_srt_RangeAxis_4b4b6e92-340a-4102-b4d4-99d96d5b8e98" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_4b4b6e92-340a-4102-b4d4-99d96d5b8e98_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_4b4b6e92-340a-4102-b4d4-99d96d5b8e98" xlink:to="loc_srt_RangeMember_4b4b6e92-340a-4102-b4d4-99d96d5b8e98_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_bd0510a7-b4b0-4f2d-92f3-c43e66fb4fd9" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_4b4b6e92-340a-4102-b4d4-99d96d5b8e98" xlink:to="loc_srt_RangeMember_bd0510a7-b4b0-4f2d-92f3-c43e66fb4fd9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_093bcdec-ef63-48c1-a2ff-0bc24d3ee744" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_bd0510a7-b4b0-4f2d-92f3-c43e66fb4fd9" xlink:to="loc_srt_MinimumMember_093bcdec-ef63-48c1-a2ff-0bc24d3ee744" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_6c5ed57c-20ad-4575-896c-85304878dc03" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_bd0510a7-b4b0-4f2d-92f3-c43e66fb4fd9" xlink:to="loc_srt_MaximumMember_6c5ed57c-20ad-4575-896c-85304878dc03" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_b70bb9b5-5faa-4b2f-a8df-ad5f5f8d85f8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7fe85411-f3b1-452b-a1fd-783915d06fc1" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_b70bb9b5-5faa-4b2f-a8df-ad5f5f8d85f8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum_9a3526bc-903f-4aba-a38b-36c016059b3a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7fe85411-f3b1-452b-a1fd-783915d06fc1" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum_9a3526bc-903f-4aba-a38b-36c016059b3a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum_85eb8e06-883d-4f00-87d7-641d685445aa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7fe85411-f3b1-452b-a1fd-783915d06fc1" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum_85eb8e06-883d-4f00-87d7-641d685445aa" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum_16b5bb75-474e-4ba3-934a-59e6cd8bf5a1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7fe85411-f3b1-452b-a1fd-783915d06fc1" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum_16b5bb75-474e-4ba3-934a-59e6cd8bf5a1" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum_447f9cc4-b04a-4fbd-b183-3be3d952522e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7fe85411-f3b1-452b-a1fd-783915d06fc1" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum_447f9cc4-b04a-4fbd-b183-3be3d952522e" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_8a63fc62-f82e-43b1-b4b1-29ab15cade63" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7fe85411-f3b1-452b-a1fd-783915d06fc1" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_8a63fc62-f82e-43b1-b4b1-29ab15cade63" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_ShareBasedCompensationArrangementByShareBasedPaymentAwardForfeitureRate_b98fd538-3e65-4047-a625-50aeac3cd289" xlink:href="lxfr-20250629.xsd#lxfr_ShareBasedCompensationArrangementByShareBasedPaymentAwardForfeitureRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7fe85411-f3b1-452b-a1fd-783915d06fc1" xlink:to="loc_lxfr_ShareBasedCompensationArrangementByShareBasedPaymentAwardForfeitureRate_b98fd538-3e65-4047-a625-50aeac3cd289" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExercisePrice_b3239872-8609-44b0-b299-c722bce87d58" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExercisePrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7fe85411-f3b1-452b-a1fd-783915d06fc1" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExercisePrice_b3239872-8609-44b0-b299-c722bce87d58" xlink:type="arc" order="7"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.luxfer.com/role/ShareholdersEquityScheduleofDividendPaidandProposedDetails" xlink:type="simple" xlink:href="lxfr-20250629.xsd#ShareholdersEquityScheduleofDividendPaidandProposedDetails"/>
  <link:definitionLink xlink:role="http://www.luxfer.com/role/ShareholdersEquityScheduleofDividendPaidandProposedDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockLineItems_9aebb6ce-4c24-4f51-b87c-849fd13eeb63" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfStockByClassTable_1bb3159d-268e-4dee-b820-f73e137e9856" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfStockByClassTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ClassOfStockLineItems_9aebb6ce-4c24-4f51-b87c-849fd13eeb63" xlink:to="loc_us-gaap_ScheduleOfStockByClassTable_1bb3159d-268e-4dee-b820-f73e137e9856" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsAxis_842be417-b0de-4255-98bb-9ea31ea31e32" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DividendsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_1bb3159d-268e-4dee-b820-f73e137e9856" xlink:to="loc_us-gaap_DividendsAxis_842be417-b0de-4255-98bb-9ea31ea31e32" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsDomain_842be417-b0de-4255-98bb-9ea31ea31e32_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DividendsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DividendsAxis_842be417-b0de-4255-98bb-9ea31ea31e32" xlink:to="loc_us-gaap_DividendsDomain_842be417-b0de-4255-98bb-9ea31ea31e32_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsDomain_c1d05013-3ac4-48f7-b97a-70b24c673947" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DividendsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DividendsAxis_842be417-b0de-4255-98bb-9ea31ea31e32" xlink:to="loc_us-gaap_DividendsDomain_c1d05013-3ac4-48f7-b97a-70b24c673947" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_O2024Q1DividendsMember_5740a048-2bcf-4cb3-aaca-8c6eaf9fd691" xlink:href="lxfr-20250629.xsd#lxfr_O2024Q1DividendsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DividendsDomain_c1d05013-3ac4-48f7-b97a-70b24c673947" xlink:to="loc_lxfr_O2024Q1DividendsMember_5740a048-2bcf-4cb3-aaca-8c6eaf9fd691" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_O2024Q2DividendsMember_1ab254fb-ce1f-4adc-a20d-9d4af7822e15" xlink:href="lxfr-20250629.xsd#lxfr_O2024Q2DividendsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DividendsDomain_c1d05013-3ac4-48f7-b97a-70b24c673947" xlink:to="loc_lxfr_O2024Q2DividendsMember_1ab254fb-ce1f-4adc-a20d-9d4af7822e15" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_O2025Q1DividendsMember_850afa8f-782c-4f1e-afb9-3ff49205a603" xlink:href="lxfr-20250629.xsd#lxfr_O2025Q1DividendsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DividendsDomain_c1d05013-3ac4-48f7-b97a-70b24c673947" xlink:to="loc_lxfr_O2025Q1DividendsMember_850afa8f-782c-4f1e-afb9-3ff49205a603" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_O2025Q2DividendsMember_012dd0ac-af88-4b72-b1ea-9d14d00263e4" xlink:href="lxfr-20250629.xsd#lxfr_O2025Q2DividendsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DividendsDomain_c1d05013-3ac4-48f7-b97a-70b24c673947" xlink:to="loc_lxfr_O2025Q2DividendsMember_012dd0ac-af88-4b72-b1ea-9d14d00263e4" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_O2024Q3DividendsMember_b8be8a4f-0060-48a9-8e46-dcd9b4378457" xlink:href="lxfr-20250629.xsd#lxfr_O2024Q3DividendsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DividendsDomain_c1d05013-3ac4-48f7-b97a-70b24c673947" xlink:to="loc_lxfr_O2024Q3DividendsMember_b8be8a4f-0060-48a9-8e46-dcd9b4378457" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_455c0565-13df-4aef-8260-0080d1c7e82c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_1bb3159d-268e-4dee-b820-f73e137e9856" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_455c0565-13df-4aef-8260-0080d1c7e82c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_455c0565-13df-4aef-8260-0080d1c7e82c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_455c0565-13df-4aef-8260-0080d1c7e82c" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_455c0565-13df-4aef-8260-0080d1c7e82c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_90c03217-5d1d-4a3b-8fc9-e16891bef853" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_455c0565-13df-4aef-8260-0080d1c7e82c" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_90c03217-5d1d-4a3b-8fc9-e16891bef853" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventMember_d76a4e9c-4835-43ae-adbf-924adf390803" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_90c03217-5d1d-4a3b-8fc9-e16891bef853" xlink:to="loc_us-gaap_SubsequentEventMember_d76a4e9c-4835-43ae-adbf-924adf390803" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockDividendsPerShareCashPaid_4cd0bdfa-ba8c-4fc1-9416-188eaffbf0c9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockDividendsPerShareCashPaid"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_9aebb6ce-4c24-4f51-b87c-849fd13eeb63" xlink:to="loc_us-gaap_CommonStockDividendsPerShareCashPaid_4cd0bdfa-ba8c-4fc1-9416-188eaffbf0c9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsCommonStock_83d1588f-a2c4-4a31-82fb-f5336b07bf95" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DividendsCommonStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_9aebb6ce-4c24-4f51-b87c-849fd13eeb63" xlink:to="loc_us-gaap_DividendsCommonStock_83d1588f-a2c4-4a31-82fb-f5336b07bf95" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsPayableCurrent_1e31861d-0628-42b5-a9c4-8c50c1be7e56" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DividendsPayableCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_9aebb6ce-4c24-4f51-b87c-849fd13eeb63" xlink:to="loc_us-gaap_DividendsPayableCurrent_1e31861d-0628-42b5-a9c4-8c50c1be7e56" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.luxfer.com/role/SegmentalInformationAdditionalInformationDetails" xlink:type="simple" xlink:href="lxfr-20250629.xsd#SegmentalInformationAdditionalInformationDetails"/>
  <link:definitionLink xlink:role="http://www.luxfer.com/role/SegmentalInformationAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_fec267db-70b9-428f-be82-d9dfa8ef2871" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentReportingInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_ddbd17eb-1b96-4744-84bf-f74ba3624819" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_fec267db-70b9-428f-be82-d9dfa8ef2871" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_ddbd17eb-1b96-4744-84bf-f74ba3624819" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementOperatingActivitiesSegmentAxis_a9f24c16-33b1-4b01-9321-eced2c5bb4eb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementOperatingActivitiesSegmentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_ddbd17eb-1b96-4744-84bf-f74ba3624819" xlink:to="loc_us-gaap_StatementOperatingActivitiesSegmentAxis_a9f24c16-33b1-4b01-9321-eced2c5bb4eb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentOperatingActivitiesDomain_a9f24c16-33b1-4b01-9321-eced2c5bb4eb_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentOperatingActivitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementOperatingActivitiesSegmentAxis_a9f24c16-33b1-4b01-9321-eced2c5bb4eb" xlink:to="loc_us-gaap_SegmentOperatingActivitiesDomain_a9f24c16-33b1-4b01-9321-eced2c5bb4eb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentOperatingActivitiesDomain_203b49b5-c312-42ed-bd50-e33f92268d0a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentOperatingActivitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementOperatingActivitiesSegmentAxis_a9f24c16-33b1-4b01-9321-eced2c5bb4eb" xlink:to="loc_us-gaap_SegmentOperatingActivitiesDomain_203b49b5-c312-42ed-bd50-e33f92268d0a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntersegmentEliminationMember_94c4e508-960b-4428-997a-dc83696a2519" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IntersegmentEliminationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentOperatingActivitiesDomain_203b49b5-c312-42ed-bd50-e33f92268d0a" xlink:to="loc_us-gaap_IntersegmentEliminationMember_94c4e508-960b-4428-997a-dc83696a2519" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfReportingUnits_ce07c5d4-d7d1-4d4a-90a0-242e3dbc37ea" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NumberOfReportingUnits"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_fec267db-70b9-428f-be82-d9dfa8ef2871" xlink:to="loc_us-gaap_NumberOfReportingUnits_ce07c5d4-d7d1-4d4a-90a0-242e3dbc37ea" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfReportableSegments_cb1a6ad3-7483-494b-8bac-99cd9372aefa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NumberOfReportableSegments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_fec267db-70b9-428f-be82-d9dfa8ef2871" xlink:to="loc_us-gaap_NumberOfReportableSegments_cb1a6ad3-7483-494b-8bac-99cd9372aefa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_NumberOfDiscontinuedOperations_524c9920-21e0-444d-9c63-c6dada1a5af2" xlink:href="lxfr-20250629.xsd#lxfr_NumberOfDiscontinuedOperations"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_fec267db-70b9-428f-be82-d9dfa8ef2871" xlink:to="loc_lxfr_NumberOfDiscontinuedOperations_524c9920-21e0-444d-9c63-c6dada1a5af2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_f3576541-25ae-4283-adf3-0b877e81bf70" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_fec267db-70b9-428f-be82-d9dfa8ef2871" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_f3576541-25ae-4283-adf3-0b877e81bf70" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.luxfer.com/role/SegmentalInformationReconciliationofConsolidatedSegmentIncomeDetails" xlink:type="simple" xlink:href="lxfr-20250629.xsd#SegmentalInformationReconciliationofConsolidatedSegmentIncomeDetails"/>
  <link:definitionLink xlink:role="http://www.luxfer.com/role/SegmentalInformationReconciliationofConsolidatedSegmentIncomeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_7a293266-1985-40cb-8ba6-9f4f741de27e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentReportingInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_c683ae8e-eb98-4231-8ba3-0defd02f8dfa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_7a293266-1985-40cb-8ba6-9f4f741de27e" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_c683ae8e-eb98-4231-8ba3-0defd02f8dfa" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsAxis_c8295034-62d9-4da8-bc33-25262d91356e" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidationItemsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_c683ae8e-eb98-4231-8ba3-0defd02f8dfa" xlink:to="loc_srt_ConsolidationItemsAxis_c8295034-62d9-4da8-bc33-25262d91356e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_c8295034-62d9-4da8-bc33-25262d91356e_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_c8295034-62d9-4da8-bc33-25262d91356e" xlink:to="loc_srt_ConsolidationItemsDomain_c8295034-62d9-4da8-bc33-25262d91356e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_562e034e-9603-42b1-b0ee-f22050711356" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_c8295034-62d9-4da8-bc33-25262d91356e" xlink:to="loc_srt_ConsolidationItemsDomain_562e034e-9603-42b1-b0ee-f22050711356" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingSegmentsMember_6d8d4b4b-45ff-4ad9-a4d6-3d996484ea6b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_562e034e-9603-42b1-b0ee-f22050711356" xlink:to="loc_us-gaap_OperatingSegmentsMember_6d8d4b4b-45ff-4ad9-a4d6-3d996484ea6b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntersegmentEliminationMember_d1330bcf-b9c8-4fb4-b09f-542f8869bdad" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IntersegmentEliminationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_562e034e-9603-42b1-b0ee-f22050711356" xlink:to="loc_us-gaap_IntersegmentEliminationMember_d1330bcf-b9c8-4fb4-b09f-542f8869bdad" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_81f55e50-bc23-46b2-b711-d2d4b7703fa6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_c683ae8e-eb98-4231-8ba3-0defd02f8dfa" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_81f55e50-bc23-46b2-b711-d2d4b7703fa6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_81f55e50-bc23-46b2-b711-d2d4b7703fa6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_81f55e50-bc23-46b2-b711-d2d4b7703fa6" xlink:to="loc_us-gaap_SegmentDomain_81f55e50-bc23-46b2-b711-d2d4b7703fa6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_867885ca-b5fa-4a8d-97a8-db2454c45b56" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_81f55e50-bc23-46b2-b711-d2d4b7703fa6" xlink:to="loc_us-gaap_SegmentDomain_867885ca-b5fa-4a8d-97a8-db2454c45b56" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_GasCylindersSegmentMember_9c6faeaf-edf1-4ae9-bc1f-f3d447646a9d" xlink:href="lxfr-20250629.xsd#lxfr_GasCylindersSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_867885ca-b5fa-4a8d-97a8-db2454c45b56" xlink:to="loc_lxfr_GasCylindersSegmentMember_9c6faeaf-edf1-4ae9-bc1f-f3d447646a9d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_ElektronSegmentMember_546ddc6d-dae8-45dd-b309-0716dfb408e5" xlink:href="lxfr-20250629.xsd#lxfr_ElektronSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_867885ca-b5fa-4a8d-97a8-db2454c45b56" xlink:to="loc_lxfr_ElektronSegmentMember_546ddc6d-dae8-45dd-b309-0716dfb408e5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_GraphicArtsMember_56df15ca-aa62-4504-93d0-cbd8c5c0695b" xlink:href="lxfr-20250629.xsd#lxfr_GraphicArtsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_867885ca-b5fa-4a8d-97a8-db2454c45b56" xlink:to="loc_lxfr_GraphicArtsMember_56df15ca-aa62-4504-93d0-cbd8c5c0695b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_47da8889-b5aa-44df-b808-e86e47585120" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_7a293266-1985-40cb-8ba6-9f4f741de27e" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_47da8889-b5aa-44df-b808-e86e47585120" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ManufacturingCosts_a4892e1d-d2a5-4c9f-a6a8-4432e5b78b12" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ManufacturingCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_7a293266-1985-40cb-8ba6-9f4f741de27e" xlink:to="loc_us-gaap_ManufacturingCosts_a4892e1d-d2a5-4c9f-a6a8-4432e5b78b12" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfGoodsAndServicesSold_866f35e0-6845-4691-95bd-8b06dcc9c3ac" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostOfGoodsAndServicesSold"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_7a293266-1985-40cb-8ba6-9f4f741de27e" xlink:to="loc_us-gaap_CostOfGoodsAndServicesSold_866f35e0-6845-4691-95bd-8b06dcc9c3ac" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingOtherItemAmount_36f6ea77-5974-4d83-a10f-65b46b96718c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentReportingOtherItemAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_7a293266-1985-40cb-8ba6-9f4f741de27e" xlink:to="loc_us-gaap_SegmentReportingOtherItemAmount_36f6ea77-5974-4d83-a10f-65b46b96718c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_AdjustedEBITDA_cc611165-f450-45a4-b37e-8cc75571583c" xlink:href="lxfr-20250629.xsd#lxfr_AdjustedEBITDA"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_7a293266-1985-40cb-8ba6-9f4f741de27e" xlink:to="loc_lxfr_AdjustedEBITDA_cc611165-f450-45a4-b37e-8cc75571583c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationDepletionAndAmortization_25c4f5a6-4a4b-40ef-9511-a9202d551a4f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DepreciationDepletionAndAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_7a293266-1985-40cb-8ba6-9f4f741de27e" xlink:to="loc_us-gaap_DepreciationDepletionAndAmortization_25c4f5a6-4a4b-40ef-9511-a9202d551a4f" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense_359f63e9-ee34-4861-a2f8-26cc44c7834c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AllocatedShareBasedCompensationExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_7a293266-1985-40cb-8ba6-9f4f741de27e" xlink:to="loc_us-gaap_AllocatedShareBasedCompensationExpense_359f63e9-ee34-4861-a2f8-26cc44c7834c" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringCharges_43a3eed1-e895-482e-99c2-9f7bcf9b91cd" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestructuringCharges"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_7a293266-1985-40cb-8ba6-9f4f741de27e" xlink:to="loc_us-gaap_RestructuringCharges_43a3eed1-e895-482e-99c2-9f7bcf9b91cd" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_DisposalGroupNotDiscontinuedOperationDisposalCostAndLossGainOnWriteDown_bb7e9daf-5670-44a6-bf5c-90a30b1643b1" xlink:href="lxfr-20250629.xsd#lxfr_DisposalGroupNotDiscontinuedOperationDisposalCostAndLossGainOnWriteDown"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_7a293266-1985-40cb-8ba6-9f4f741de27e" xlink:to="loc_lxfr_DisposalGroupNotDiscontinuedOperationDisposalCostAndLossGainOnWriteDown_bb7e9daf-5670-44a6-bf5c-90a30b1643b1" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetPeriodicDefinedBenefitsExpenseReversalOfExpenseExcludingServiceCostComponent_9e02c951-515f-4f5f-9828-6575b6502f7c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetPeriodicDefinedBenefitsExpenseReversalOfExpenseExcludingServiceCostComponent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_7a293266-1985-40cb-8ba6-9f4f741de27e" xlink:to="loc_us-gaap_NetPeriodicDefinedBenefitsExpenseReversalOfExpenseExcludingServiceCostComponent_9e02c951-515f-4f5f-9828-6575b6502f7c" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeExpenseNet_b3efb1f2-38f3-4845-a42a-854610fe1da9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestIncomeExpenseNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_7a293266-1985-40cb-8ba6-9f4f741de27e" xlink:to="loc_us-gaap_InterestIncomeExpenseNet_b3efb1f2-38f3-4845-a42a-854610fe1da9" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_13025f70-2a8f-4d9d-890c-0ad5214ea109" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_7a293266-1985-40cb-8ba6-9f4f741de27e" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_13025f70-2a8f-4d9d-890c-0ad5214ea109" xlink:type="arc" order="11"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.luxfer.com/role/SegmentalInformationFinancialInformationbyReportableSegmentDetails" xlink:type="simple" xlink:href="lxfr-20250629.xsd#SegmentalInformationFinancialInformationbyReportableSegmentDetails"/>
  <link:definitionLink xlink:role="http://www.luxfer.com/role/SegmentalInformationFinancialInformationbyReportableSegmentDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_87d5d8c7-a67e-4e80-bbe2-9cd1cc91b267" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentReportingInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_b199354e-4fd9-4eff-bf19-7ac3d32fa7c0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_87d5d8c7-a67e-4e80-bbe2-9cd1cc91b267" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_b199354e-4fd9-4eff-bf19-7ac3d32fa7c0" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsAxis_b9be228f-ac98-4c44-ad8a-c2af7ba4c9b7" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidationItemsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_b199354e-4fd9-4eff-bf19-7ac3d32fa7c0" xlink:to="loc_srt_ConsolidationItemsAxis_b9be228f-ac98-4c44-ad8a-c2af7ba4c9b7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_b9be228f-ac98-4c44-ad8a-c2af7ba4c9b7_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_b9be228f-ac98-4c44-ad8a-c2af7ba4c9b7" xlink:to="loc_srt_ConsolidationItemsDomain_b9be228f-ac98-4c44-ad8a-c2af7ba4c9b7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_e29db870-52a1-421a-9a90-931ebad30c93" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_b9be228f-ac98-4c44-ad8a-c2af7ba4c9b7" xlink:to="loc_srt_ConsolidationItemsDomain_e29db870-52a1-421a-9a90-931ebad30c93" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingSegmentsMember_9ec3c79d-ce1f-4858-a4a3-01e0cd8ac657" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_e29db870-52a1-421a-9a90-931ebad30c93" xlink:to="loc_us-gaap_OperatingSegmentsMember_9ec3c79d-ce1f-4858-a4a3-01e0cd8ac657" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateNonSegmentMember_a0502c5d-e919-4212-b688-8e679eada8df" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CorporateNonSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_e29db870-52a1-421a-9a90-931ebad30c93" xlink:to="loc_us-gaap_CorporateNonSegmentMember_a0502c5d-e919-4212-b688-8e679eada8df" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_4b3b4769-93bc-4a98-ae78-04587b65e3b1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_b199354e-4fd9-4eff-bf19-7ac3d32fa7c0" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_4b3b4769-93bc-4a98-ae78-04587b65e3b1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_4b3b4769-93bc-4a98-ae78-04587b65e3b1_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_4b3b4769-93bc-4a98-ae78-04587b65e3b1" xlink:to="loc_us-gaap_SegmentDomain_4b3b4769-93bc-4a98-ae78-04587b65e3b1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_a8bef7b8-e077-4ec0-9124-3aafaaf126cb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_4b3b4769-93bc-4a98-ae78-04587b65e3b1" xlink:to="loc_us-gaap_SegmentDomain_a8bef7b8-e077-4ec0-9124-3aafaaf126cb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_GasCylindersSegmentMember_3a4fa2ae-8227-4334-a9e9-7e8981b28f4b" xlink:href="lxfr-20250629.xsd#lxfr_GasCylindersSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_a8bef7b8-e077-4ec0-9124-3aafaaf126cb" xlink:to="loc_lxfr_GasCylindersSegmentMember_3a4fa2ae-8227-4334-a9e9-7e8981b28f4b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_ElektronSegmentMember_1d9ce0b6-a338-4029-bb84-9720d910a839" xlink:href="lxfr-20250629.xsd#lxfr_ElektronSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_a8bef7b8-e077-4ec0-9124-3aafaaf126cb" xlink:to="loc_lxfr_ElektronSegmentMember_1d9ce0b6-a338-4029-bb84-9720d910a839" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_GraphicArtsMember_6ecb4a74-2405-4163-b756-2bc616c03918" xlink:href="lxfr-20250629.xsd#lxfr_GraphicArtsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_a8bef7b8-e077-4ec0-9124-3aafaaf126cb" xlink:to="loc_lxfr_GraphicArtsMember_6ecb4a74-2405-4163-b756-2bc616c03918" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementOperatingActivitiesSegmentAxis_5b55e5a1-e56b-4d63-b25c-39431c5ac349" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementOperatingActivitiesSegmentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_b199354e-4fd9-4eff-bf19-7ac3d32fa7c0" xlink:to="loc_us-gaap_StatementOperatingActivitiesSegmentAxis_5b55e5a1-e56b-4d63-b25c-39431c5ac349" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentOperatingActivitiesDomain_5b55e5a1-e56b-4d63-b25c-39431c5ac349_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentOperatingActivitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementOperatingActivitiesSegmentAxis_5b55e5a1-e56b-4d63-b25c-39431c5ac349" xlink:to="loc_us-gaap_SegmentOperatingActivitiesDomain_5b55e5a1-e56b-4d63-b25c-39431c5ac349_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentOperatingActivitiesDomain_e9c33f09-188e-4dbe-960b-ad3c3a8e46e7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentOperatingActivitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementOperatingActivitiesSegmentAxis_5b55e5a1-e56b-4d63-b25c-39431c5ac349" xlink:to="loc_us-gaap_SegmentOperatingActivitiesDomain_e9c33f09-188e-4dbe-960b-ad3c3a8e46e7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDiscontinuedOperationsMember_393e0339-9d68-40f4-840d-ac42922a00df" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDiscontinuedOperationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentOperatingActivitiesDomain_e9c33f09-188e-4dbe-960b-ad3c3a8e46e7" xlink:to="loc_us-gaap_SegmentDiscontinuedOperationsMember_393e0339-9d68-40f4-840d-ac42922a00df" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationDepletionAndAmortization_7616e814-28c0-4b63-84ef-0944ca0e2b6c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DepreciationDepletionAndAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_87d5d8c7-a67e-4e80-bbe2-9cd1cc91b267" xlink:to="loc_us-gaap_DepreciationDepletionAndAmortization_7616e814-28c0-4b63-84ef-0944ca0e2b6c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringCharges_20d34a8a-7970-45fb-bec4-126e4732bed4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestructuringCharges"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_87d5d8c7-a67e-4e80-bbe2-9cd1cc91b267" xlink:to="loc_us-gaap_RestructuringCharges_20d34a8a-7970-45fb-bec4-126e4732bed4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_038d36f6-1b43-4a21-a98a-03c2237d6970" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Assets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_87d5d8c7-a67e-4e80-bbe2-9cd1cc91b267" xlink:to="loc_us-gaap_Assets_038d36f6-1b43-4a21-a98a-03c2237d6970" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_CapitalExpenditureCashAndNoncash_6cc88bcd-839f-4eb2-ae1c-5e15f48a0968" xlink:href="lxfr-20250629.xsd#lxfr_CapitalExpenditureCashAndNoncash"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_87d5d8c7-a67e-4e80-bbe2-9cd1cc91b267" xlink:to="loc_lxfr_CapitalExpenditureCashAndNoncash_6cc88bcd-839f-4eb2-ae1c-5e15f48a0968" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.luxfer.com/role/SegmentalInformationGeographicInformationbyRegionDetails" xlink:type="simple" xlink:href="lxfr-20250629.xsd#SegmentalInformationGeographicInformationbyRegionDetails"/>
  <link:definitionLink xlink:role="http://www.luxfer.com/role/SegmentalInformationGeographicInformationbyRegionDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_16a3ef35-bcc5-4ed6-89b2-bae303390b5c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_7708d1ad-a835-4b0e-b46c-45f7ca35ce3b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_16a3ef35-bcc5-4ed6-89b2-bae303390b5c" xlink:to="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_7708d1ad-a835-4b0e-b46c-45f7ca35ce3b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_67d40adb-9395-4183-8d70-742c6b31b3cd" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_7708d1ad-a835-4b0e-b46c-45f7ca35ce3b" xlink:to="loc_srt_StatementGeographicalAxis_67d40adb-9395-4183-8d70-742c6b31b3cd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_67d40adb-9395-4183-8d70-742c6b31b3cd_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_67d40adb-9395-4183-8d70-742c6b31b3cd" xlink:to="loc_srt_SegmentGeographicalDomain_67d40adb-9395-4183-8d70-742c6b31b3cd_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_fc50ffd1-0fc0-4a84-818e-02eabec155d9" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_67d40adb-9395-4183-8d70-742c6b31b3cd" xlink:to="loc_srt_SegmentGeographicalDomain_fc50ffd1-0fc0-4a84-818e-02eabec155d9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_US_7d008235-b025-4df9-aefd-6552d13ceaec" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_US"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_fc50ffd1-0fc0-4a84-818e-02eabec155d9" xlink:to="loc_country_US_7d008235-b025-4df9-aefd-6552d13ceaec" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_GB_10a485d8-f9dc-41c5-8def-caa3c5ff6ed7" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_GB"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_fc50ffd1-0fc0-4a84-818e-02eabec155d9" xlink:to="loc_country_GB_10a485d8-f9dc-41c5-8def-caa3c5ff6ed7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_CA_1beb9868-8508-4e31-9775-2f0a8673a0d2" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_CA"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_fc50ffd1-0fc0-4a84-818e-02eabec155d9" xlink:to="loc_country_CA_1beb9868-8508-4e31-9775-2f0a8673a0d2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AsiaPacificMember_2ccb1a91-10a5-4f51-8eb4-350ce1031aae" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_AsiaPacificMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_fc50ffd1-0fc0-4a84-818e-02eabec155d9" xlink:to="loc_srt_AsiaPacificMember_2ccb1a91-10a5-4f51-8eb4-350ce1031aae" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_a3dec40e-28f1-4716-9eff-1f31cbafc9dc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_16a3ef35-bcc5-4ed6-89b2-bae303390b5c" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentNet_a3dec40e-28f1-4716-9eff-1f31cbafc9dc" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.luxfer.com/role/SegmentalInformationGeographicInformationbyRegionDetails_1" xlink:type="simple" xlink:href="lxfr-20250629.xsd#SegmentalInformationGeographicInformationbyRegionDetails_1"/>
  <link:definitionLink xlink:role="http://www.luxfer.com/role/SegmentalInformationGeographicInformationbyRegionDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_f1a96ea0-9980-4cec-acff-a723c25ce137" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_33bb2eef-242f-4668-b760-c5825546e1f1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_f1a96ea0-9980-4cec-acff-a723c25ce137" xlink:to="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_33bb2eef-242f-4668-b760-c5825546e1f1" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_00d85464-83fe-4624-a61f-4ef1ef2d895d" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_33bb2eef-242f-4668-b760-c5825546e1f1" xlink:to="loc_srt_StatementGeographicalAxis_00d85464-83fe-4624-a61f-4ef1ef2d895d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_00d85464-83fe-4624-a61f-4ef1ef2d895d_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_00d85464-83fe-4624-a61f-4ef1ef2d895d" xlink:to="loc_srt_SegmentGeographicalDomain_00d85464-83fe-4624-a61f-4ef1ef2d895d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_13836359-c237-43f4-b297-c1d8677a2b4b" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_00d85464-83fe-4624-a61f-4ef1ef2d895d" xlink:to="loc_srt_SegmentGeographicalDomain_13836359-c237-43f4-b297-c1d8677a2b4b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_TopFiveCountriesMember_2cac1186-f711-40de-9b3c-97c31eadd1b5" xlink:href="lxfr-20250629.xsd#lxfr_TopFiveCountriesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_13836359-c237-43f4-b297-c1d8677a2b4b" xlink:to="loc_lxfr_TopFiveCountriesMember_2cac1186-f711-40de-9b3c-97c31eadd1b5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_US_53bd2c01-aa8f-42a1-a8bd-ee0cbce2a809" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_US"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_lxfr_TopFiveCountriesMember_2cac1186-f711-40de-9b3c-97c31eadd1b5" xlink:to="loc_country_US_53bd2c01-aa8f-42a1-a8bd-ee0cbce2a809" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_GB_ed1e3599-daae-4ebc-aa2a-d038a2a10189" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_GB"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_lxfr_TopFiveCountriesMember_2cac1186-f711-40de-9b3c-97c31eadd1b5" xlink:to="loc_country_GB_ed1e3599-daae-4ebc-aa2a-d038a2a10189" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_JP_ac5a5432-42bb-4fdb-a196-7b84583b7c52" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_JP"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_lxfr_TopFiveCountriesMember_2cac1186-f711-40de-9b3c-97c31eadd1b5" xlink:to="loc_country_JP_ac5a5432-42bb-4fdb-a196-7b84583b7c52" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_DE_5fcc2499-665a-4725-aff5-9468502c89f6" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_DE"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_lxfr_TopFiveCountriesMember_2cac1186-f711-40de-9b3c-97c31eadd1b5" xlink:to="loc_country_DE_5fcc2499-665a-4725-aff5-9468502c89f6" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_CA_b11f4683-2804-4715-baee-08aa735cf9b4" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_CA"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_lxfr_TopFiveCountriesMember_2cac1186-f711-40de-9b3c-97c31eadd1b5" xlink:to="loc_country_CA_b11f4683-2804-4715-baee-08aa735cf9b4" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_RestOfEuropeMember_dcf97bc1-45b2-419b-85d9-d7b2464e53d8" xlink:href="lxfr-20250629.xsd#lxfr_RestOfEuropeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_13836359-c237-43f4-b297-c1d8677a2b4b" xlink:to="loc_lxfr_RestOfEuropeMember_dcf97bc1-45b2-419b-85d9-d7b2464e53d8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AsiaPacificMember_9a143399-6d05-4005-9bd7-c482c897feb9" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_AsiaPacificMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_13836359-c237-43f4-b297-c1d8677a2b4b" xlink:to="loc_srt_AsiaPacificMember_9a143399-6d05-4005-9bd7-c482c897feb9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_OtherGeographicRegionMember_15ba8159-426d-46ce-95d0-fd448dd9d823" xlink:href="lxfr-20250629.xsd#lxfr_OtherGeographicRegionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_13836359-c237-43f4-b297-c1d8677a2b4b" xlink:to="loc_lxfr_OtherGeographicRegionMember_15ba8159-426d-46ce-95d0-fd448dd9d823" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_5a1aad72-dee7-4311-b415-721b5b17fc34" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_33bb2eef-242f-4668-b760-c5825546e1f1" xlink:to="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_5a1aad72-dee7-4311-b415-721b5b17fc34" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_5a1aad72-dee7-4311-b415-721b5b17fc34_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_5a1aad72-dee7-4311-b415-721b5b17fc34" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_5a1aad72-dee7-4311-b415-721b5b17fc34_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_78e79ad8-e6b8-4615-864d-f297799a6427" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_5a1aad72-dee7-4311-b415-721b5b17fc34" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_78e79ad8-e6b8-4615-864d-f297799a6427" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerMember_248bfe1c-190b-4539-90bf-83de915f7b97" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskBenchmarkDomain_78e79ad8-e6b8-4615-864d-f297799a6427" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerMember_248bfe1c-190b-4539-90bf-83de915f7b97" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByTypeAxis_28383e31-a150-454c-bffb-c8628223554c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_33bb2eef-242f-4668-b760-c5825546e1f1" xlink:to="loc_us-gaap_ConcentrationRiskByTypeAxis_28383e31-a150-454c-bffb-c8628223554c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_28383e31-a150-454c-bffb-c8628223554c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_28383e31-a150-454c-bffb-c8628223554c" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_28383e31-a150-454c-bffb-c8628223554c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_73cb3ca0-299d-45e9-8711-0b9e209c83e8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_28383e31-a150-454c-bffb-c8628223554c" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_73cb3ca0-299d-45e9-8711-0b9e209c83e8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeographicConcentrationRiskMember_d680e94d-e699-47af-bd81-48bc31263e6f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GeographicConcentrationRiskMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskTypeDomain_73cb3ca0-299d-45e9-8711-0b9e209c83e8" xlink:to="loc_us-gaap_GeographicConcentrationRiskMember_d680e94d-e699-47af-bd81-48bc31263e6f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_23d8c156-d5b6-4f2d-8436-d550b21b1a5f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_f1a96ea0-9980-4cec-acff-a723c25ce137" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_23d8c156-d5b6-4f2d-8436-d550b21b1a5f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskPercentage1_4d95423c-a130-4d8f-93c2-7b60320fbd6b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskPercentage1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_f1a96ea0-9980-4cec-acff-a723c25ce137" xlink:to="loc_us-gaap_ConcentrationRiskPercentage1_4d95423c-a130-4d8f-93c2-7b60320fbd6b" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.luxfer.com/role/CommitmentsandContingenciesAdditionalInformationDetails" xlink:type="simple" xlink:href="lxfr-20250629.xsd#CommitmentsandContingenciesAdditionalInformationDetails"/>
  <link:definitionLink xlink:role="http://www.luxfer.com/role/CommitmentsandContingenciesAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingenciesLineItems_854ac0fc-2dbc-4272-8263-d9e5308a82ba" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LossContingenciesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingenciesTable_5bee7266-3643-4bd1-b2a9-cec41ba5c25b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LossContingenciesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LossContingenciesLineItems_854ac0fc-2dbc-4272-8263-d9e5308a82ba" xlink:to="loc_us-gaap_LossContingenciesTable_5bee7266-3643-4bd1-b2a9-cec41ba5c25b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_8f5591ac-a82d-410e-b0fd-56e383e5db73" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_5bee7266-3643-4bd1-b2a9-cec41ba5c25b" xlink:to="loc_us-gaap_DebtInstrumentAxis_8f5591ac-a82d-410e-b0fd-56e383e5db73" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_8f5591ac-a82d-410e-b0fd-56e383e5db73_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_8f5591ac-a82d-410e-b0fd-56e383e5db73" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_8f5591ac-a82d-410e-b0fd-56e383e5db73_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_9b1a4ddb-dc10-493b-b883-49aeaa718e54" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_8f5591ac-a82d-410e-b0fd-56e383e5db73" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_9b1a4ddb-dc10-493b-b883-49aeaa718e54" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_CommittedBankingFacilitiesMember_6211b66d-2c81-4029-8184-5ec92fa7441b" xlink:href="lxfr-20250629.xsd#lxfr_CommittedBankingFacilitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_9b1a4ddb-dc10-493b-b883-49aeaa718e54" xlink:to="loc_lxfr_CommittedBankingFacilitiesMember_6211b66d-2c81-4029-8184-5ec92fa7441b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_ec91ea94-77a1-41fa-b948-5bac43073bee" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_5bee7266-3643-4bd1-b2a9-cec41ba5c25b" xlink:to="loc_us-gaap_CreditFacilityAxis_ec91ea94-77a1-41fa-b948-5bac43073bee" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_ec91ea94-77a1-41fa-b948-5bac43073bee_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_ec91ea94-77a1-41fa-b948-5bac43073bee" xlink:to="loc_us-gaap_CreditFacilityDomain_ec91ea94-77a1-41fa-b948-5bac43073bee_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_1f4d73cd-efe9-4051-bd76-7d2ce46240f6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_ec91ea94-77a1-41fa-b948-5bac43073bee" xlink:to="loc_us-gaap_CreditFacilityDomain_1f4d73cd-efe9-4051-bd76-7d2ce46240f6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_641b24b5-69f3-4a0c-bc6b-d7e0a9a8df62" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevolvingCreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_1f4d73cd-efe9-4051-bd76-7d2ce46240f6" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_641b24b5-69f3-4a0c-bc6b-d7e0a9a8df62" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_e1fe8693-cf28-47b6-aa8f-770bf03cfeef" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_5bee7266-3643-4bd1-b2a9-cec41ba5c25b" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_e1fe8693-cf28-47b6-aa8f-770bf03cfeef" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_e1fe8693-cf28-47b6-aa8f-770bf03cfeef_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_e1fe8693-cf28-47b6-aa8f-770bf03cfeef" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_e1fe8693-cf28-47b6-aa8f-770bf03cfeef_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_01f368a7-a109-4026-8274-db18030467d2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_e1fe8693-cf28-47b6-aa8f-770bf03cfeef" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_01f368a7-a109-4026-8274-db18030467d2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventMember_b63f2088-035b-4043-85ff-df04c8be7b41" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_01f368a7-a109-4026-8274-db18030467d2" xlink:to="loc_us-gaap_SubsequentEventMember_b63f2088-035b-4043-85ff-df04c8be7b41" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_23a21901-3503-4671-90b6-cd67a1b1116b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_854ac0fc-2dbc-4272-8263-d9e5308a82ba" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_23a21901-3503-4671-90b6-cd67a1b1116b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentCarryingAmount_b84dd62a-bd8e-4411-9857-f60e40664ab7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentCarryingAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_854ac0fc-2dbc-4272-8263-d9e5308a82ba" xlink:to="loc_us-gaap_DebtInstrumentCarryingAmount_b84dd62a-bd8e-4411-9857-f60e40664ab7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_LineOfCreditFacilityAccordionFeatureIncreaseLimit_a08e5d12-bc53-40e1-8ca7-dc17a771662f" xlink:href="lxfr-20250629.xsd#lxfr_LineOfCreditFacilityAccordionFeatureIncreaseLimit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_854ac0fc-2dbc-4272-8263-d9e5308a82ba" xlink:to="loc_lxfr_LineOfCreditFacilityAccordionFeatureIncreaseLimit_a08e5d12-bc53-40e1-8ca7-dc17a771662f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoninterestIncomeOtherOperatingIncome_675a296a-416f-4fd5-90f6-20d9f315a445" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NoninterestIncomeOtherOperatingIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_854ac0fc-2dbc-4272-8263-d9e5308a82ba" xlink:to="loc_us-gaap_NoninterestIncomeOtherOperatingIncome_675a296a-416f-4fd5-90f6-20d9f315a445" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InsuranceRecoveries_9f8a3cd1-d316-4420-b684-e0cbf400a8dc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InsuranceRecoveries"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_854ac0fc-2dbc-4272-8263-d9e5308a82ba" xlink:to="loc_us-gaap_InsuranceRecoveries_9f8a3cd1-d316-4420-b684-e0cbf400a8dc" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InsuranceSettlementsReceivable_487afbe4-5c09-42ff-b5f0-f775ec04e311" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InsuranceSettlementsReceivable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_854ac0fc-2dbc-4272-8263-d9e5308a82ba" xlink:to="loc_us-gaap_InsuranceSettlementsReceivable_487afbe4-5c09-42ff-b5f0-f775ec04e311" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.luxfer.com/role/CommitmentsandContingenciesScheduleofUncommittedFacilitiesDetails" xlink:type="simple" xlink:href="lxfr-20250629.xsd#CommitmentsandContingenciesScheduleofUncommittedFacilitiesDetails"/>
  <link:definitionLink xlink:role="http://www.luxfer.com/role/CommitmentsandContingenciesScheduleofUncommittedFacilitiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingenciesLineItems_688dbb17-156a-47ba-a8f4-28171c1879d6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LossContingenciesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingenciesTable_878d426f-0ca9-4a04-8a26-bdb79223ec10" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LossContingenciesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LossContingenciesLineItems_688dbb17-156a-47ba-a8f4-28171c1879d6" xlink:to="loc_us-gaap_LossContingenciesTable_878d426f-0ca9-4a04-8a26-bdb79223ec10" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_2365e841-ebc9-4ca6-9a0b-79e61adc1798" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_878d426f-0ca9-4a04-8a26-bdb79223ec10" xlink:to="loc_us-gaap_DebtInstrumentAxis_2365e841-ebc9-4ca6-9a0b-79e61adc1798" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_2365e841-ebc9-4ca6-9a0b-79e61adc1798_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_2365e841-ebc9-4ca6-9a0b-79e61adc1798" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_2365e841-ebc9-4ca6-9a0b-79e61adc1798_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_0a2c2f97-ee4b-498b-8148-5db149bddbef" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_2365e841-ebc9-4ca6-9a0b-79e61adc1798" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_0a2c2f97-ee4b-498b-8148-5db149bddbef" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_BondingFacilityForBankGuaranteesMember_9229d5c9-f222-4d32-b9fb-4e9802cec3b0" xlink:href="lxfr-20250629.xsd#lxfr_BondingFacilityForBankGuaranteesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_0a2c2f97-ee4b-498b-8148-5db149bddbef" xlink:to="loc_lxfr_BondingFacilityForBankGuaranteesMember_9229d5c9-f222-4d32-b9fb-4e9802cec3b0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LetterOfCreditMember_a690bf28-a447-46fe-bad9-0146f7379347" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LetterOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_0a2c2f97-ee4b-498b-8148-5db149bddbef" xlink:to="loc_us-gaap_LetterOfCreditMember_a690bf28-a447-46fe-bad9-0146f7379347" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_BondingFacilityForBankGuaranteesLetterOfCreditAndBankOverdraftsMember_c74addc2-61c1-4fae-aa42-f14b935f0bcf" xlink:href="lxfr-20250629.xsd#lxfr_BondingFacilityForBankGuaranteesLetterOfCreditAndBankOverdraftsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_0a2c2f97-ee4b-498b-8148-5db149bddbef" xlink:to="loc_lxfr_BondingFacilityForBankGuaranteesLetterOfCreditAndBankOverdraftsMember_c74addc2-61c1-4fae-aa42-f14b935f0bcf" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_c3493a61-578f-4d64-b1db-8a1753d05e62" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_878d426f-0ca9-4a04-8a26-bdb79223ec10" xlink:to="loc_us-gaap_CreditFacilityAxis_c3493a61-578f-4d64-b1db-8a1753d05e62" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_c3493a61-578f-4d64-b1db-8a1753d05e62_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_c3493a61-578f-4d64-b1db-8a1753d05e62" xlink:to="loc_us-gaap_CreditFacilityDomain_c3493a61-578f-4d64-b1db-8a1753d05e62_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_0195dd7c-870e-4fae-a8b4-96b0768c414d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_c3493a61-578f-4d64-b1db-8a1753d05e62" xlink:to="loc_us-gaap_CreditFacilityDomain_0195dd7c-870e-4fae-a8b4-96b0768c414d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BankOverdraftsMember_e88e7472-5ff8-4544-9501-a34c245096d3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BankOverdraftsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_0195dd7c-870e-4fae-a8b4-96b0768c414d" xlink:to="loc_us-gaap_BankOverdraftsMember_e88e7472-5ff8-4544-9501-a34c245096d3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_e685e459-fd12-4206-a8c7-7abc78d9f7ae" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_688dbb17-156a-47ba-a8f4-28171c1879d6" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_e685e459-fd12-4206-a8c7-7abc78d9f7ae" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentCarryingAmount_3a8670b7-fbbe-414c-a18d-6f27c9451ce5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentCarryingAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_688dbb17-156a-47ba-a8f4-28171c1879d6" xlink:to="loc_us-gaap_DebtInstrumentCarryingAmount_3a8670b7-fbbe-414c-a18d-6f27c9451ce5" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.luxfer.com/role/SubsequentEventsDetails" xlink:type="simple" xlink:href="lxfr-20250629.xsd#SubsequentEventsDetails"/>
  <link:definitionLink xlink:role="http://www.luxfer.com/role/SubsequentEventsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventLineItems_41b09312-f2f3-408d-a255-478f7a7a05b5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTable_465b768a-95c5-490e-93dd-b43fbbc8697c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SubsequentEventLineItems_41b09312-f2f3-408d-a255-478f7a7a05b5" xlink:to="loc_us-gaap_SubsequentEventTable_465b768a-95c5-490e-93dd-b43fbbc8697c" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_4095194c-6425-4a9d-aba1-cfeba6f0254b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsequentEventTable_465b768a-95c5-490e-93dd-b43fbbc8697c" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_4095194c-6425-4a9d-aba1-cfeba6f0254b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_4095194c-6425-4a9d-aba1-cfeba6f0254b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_4095194c-6425-4a9d-aba1-cfeba6f0254b" xlink:to="loc_us-gaap_SegmentDomain_4095194c-6425-4a9d-aba1-cfeba6f0254b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_71b3890f-4c48-45db-b774-2fb0733a5914" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_4095194c-6425-4a9d-aba1-cfeba6f0254b" xlink:to="loc_us-gaap_SegmentDomain_71b3890f-4c48-45db-b774-2fb0733a5914" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_GraphicArtsMember_d2ebadd8-38ae-4783-b41f-85bbe171e232" xlink:href="lxfr-20250629.xsd#lxfr_GraphicArtsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_71b3890f-4c48-45db-b774-2fb0733a5914" xlink:to="loc_lxfr_GraphicArtsMember_d2ebadd8-38ae-4783-b41f-85bbe171e232" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_lxfr_SegmentRevenueContribution_98ca5b81-37a6-4f9a-a3b8-b8f7e216db53" xlink:href="lxfr-20250629.xsd#lxfr_SegmentRevenueContribution"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventLineItems_41b09312-f2f3-408d-a255-478f7a7a05b5" xlink:to="loc_lxfr_SegmentRevenueContribution_98ca5b81-37a6-4f9a-a3b8-b8f7e216db53" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://fasb.org/us-gaap/role/eedm/ExtensibleEnumerationLists" xlink:type="simple" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-roles-2025.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/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementAbstract"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringSettlementAndImpairmentProvisions" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestructuringSettlementAndImpairmentProvisions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementAbstract" xlink:to="loc_us-gaap_RestructuringSettlementAndImpairmentProvisions" xlink:type="arc" order="691"/>
  </link:definitionLink>
</link:linkbase>
