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

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2024 Workiva-->
<!--r:e990fc73-201e-4314-a9a4-6489dd3323ff,g:4c7742d7-4515-4f97-88f7-71ce24647d3d-->
<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.insperity.com/role/DocumentandEntityInformation" xlink:type="simple" xlink:href="nsp-20240331.xsd#DocumentandEntityInformation"/>
  <link:definitionLink xlink:role="http://www.insperity.com/role/DocumentandEntityInformation" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityInformationLineItems_a97052a5-ebce-49c4-ab25-8692c5b2386a" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntitiesTable_43bc2281-30d9-444a-a7b2-d7b1693f7693" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntitiesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_dei_EntityInformationLineItems_a97052a5-ebce-49c4-ab25-8692c5b2386a" xlink:to="loc_dei_EntitiesTable_43bc2281-30d9-444a-a7b2-d7b1693f7693" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityListingsExchangeAxis_677f8a1f-07b2-4f8d-baeb-e611ce816c37" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityListingsExchangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_dei_EntitiesTable_43bc2281-30d9-444a-a7b2-d7b1693f7693" xlink:to="loc_dei_EntityListingsExchangeAxis_677f8a1f-07b2-4f8d-baeb-e611ce816c37" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_ExchangeDomain_677f8a1f-07b2-4f8d-baeb-e611ce816c37_default" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_ExchangeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_EntityListingsExchangeAxis_677f8a1f-07b2-4f8d-baeb-e611ce816c37" xlink:to="loc_dei_ExchangeDomain_677f8a1f-07b2-4f8d-baeb-e611ce816c37_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_ExchangeDomain_8875ba6c-0916-480b-9690-4c33f6311264" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_ExchangeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_EntityListingsExchangeAxis_677f8a1f-07b2-4f8d-baeb-e611ce816c37" xlink:to="loc_dei_ExchangeDomain_8875ba6c-0916-480b-9690-4c33f6311264" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_6ace410d-610b-4960-9e3e-2925fadc651a" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_ExchangeDomain_8875ba6c-0916-480b-9690-4c33f6311264" xlink:to="loc_us-gaap_CommonStockMember_6ace410d-610b-4960-9e3e-2925fadc651a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_Security12bTitle_2c6ee8cc-a49f-41db-a91a-ce0f22a3cd55" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_Security12bTitle"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_a97052a5-ebce-49c4-ab25-8692c5b2386a" xlink:to="loc_dei_Security12bTitle_2c6ee8cc-a49f-41db-a91a-ce0f22a3cd55" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_TradingSymbol_58f3c0be-3f52-4254-b181-456b3e63b1e8" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_TradingSymbol"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_a97052a5-ebce-49c4-ab25-8692c5b2386a" xlink:to="loc_dei_TradingSymbol_58f3c0be-3f52-4254-b181-456b3e63b1e8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SecurityExchangeName_2b5e8bb9-d2ce-4537-84eb-169f913d71f4" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_SecurityExchangeName"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_a97052a5-ebce-49c4-ab25-8692c5b2386a" xlink:to="loc_dei_SecurityExchangeName_2b5e8bb9-d2ce-4537-84eb-169f913d71f4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityRegistrantName_9a3ca051-993f-4091-b338-735cb47e87a8" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityRegistrantName"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_a97052a5-ebce-49c4-ab25-8692c5b2386a" xlink:to="loc_dei_EntityRegistrantName_9a3ca051-993f-4091-b338-735cb47e87a8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityEmergingGrowthCompany_ddf3ee3d-fefe-4220-8186-c974e96f986e" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityEmergingGrowthCompany"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_a97052a5-ebce-49c4-ab25-8692c5b2386a" xlink:to="loc_dei_EntityEmergingGrowthCompany_ddf3ee3d-fefe-4220-8186-c974e96f986e" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntitySmallBusiness_bfa9dab8-3984-48a3-8f1f-5fbd9ca77207" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntitySmallBusiness"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_a97052a5-ebce-49c4-ab25-8692c5b2386a" xlink:to="loc_dei_EntitySmallBusiness_bfa9dab8-3984-48a3-8f1f-5fbd9ca77207" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.insperity.com/role/CONSOLIDATEDSTATEMENTOFSTOCKHOLDERSEQUITYUnaudited" xlink:type="simple" xlink:href="nsp-20240331.xsd#CONSOLIDATEDSTATEMENTOFSTOCKHOLDERSEQUITYUnaudited"/>
  <link:definitionLink xlink:role="http://www.insperity.com/role/CONSOLIDATEDSTATEMENTOFSTOCKHOLDERSEQUITYUnaudited" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_e39fcc0f-bec5-42be-bd6b-866808179312" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_d8497bf4-316e-4aab-97df-8065e8402b79" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_e39fcc0f-bec5-42be-bd6b-866808179312" xlink:to="loc_us-gaap_StatementTable_d8497bf4-316e-4aab-97df-8065e8402b79" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_70a81845-a6f2-458e-af64-860973ac6767" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_d8497bf4-316e-4aab-97df-8065e8402b79" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_70a81845-a6f2-458e-af64-860973ac6767" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_70a81845-a6f2-458e-af64-860973ac6767_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_70a81845-a6f2-458e-af64-860973ac6767" xlink:to="loc_us-gaap_EquityComponentDomain_70a81845-a6f2-458e-af64-860973ac6767_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_a3600d79-a6ba-4579-b6dc-9cc8fc9fa161" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_70a81845-a6f2-458e-af64-860973ac6767" xlink:to="loc_us-gaap_EquityComponentDomain_a3600d79-a6ba-4579-b6dc-9cc8fc9fa161" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_d747fef6-fa45-4e6f-ae1e-524f13e37d5e" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_a3600d79-a6ba-4579-b6dc-9cc8fc9fa161" xlink:to="loc_us-gaap_CommonStockMember_d747fef6-fa45-4e6f-ae1e-524f13e37d5e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember_7325fa54-0de6-4403-b76a-4d39ebba45a8" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AdditionalPaidInCapitalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_a3600d79-a6ba-4579-b6dc-9cc8fc9fa161" xlink:to="loc_us-gaap_AdditionalPaidInCapitalMember_7325fa54-0de6-4403-b76a-4d39ebba45a8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockCommonMember_3d26ece3-2d32-42ef-8dec-b06a534bf168" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_TreasuryStockCommonMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_a3600d79-a6ba-4579-b6dc-9cc8fc9fa161" xlink:to="loc_us-gaap_TreasuryStockCommonMember_3d26ece3-2d32-42ef-8dec-b06a534bf168" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsMember_26e43aa4-fdec-4fa0-99e2-d2126cd88635" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RetainedEarningsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_a3600d79-a6ba-4579-b6dc-9cc8fc9fa161" xlink:to="loc_us-gaap_RetainedEarningsMember_26e43aa4-fdec-4fa0-99e2-d2126cd88635" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharesIssued_3e3a9fef-2c16-47ac-a63a-5209d96f51f1" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SharesIssued"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_e39fcc0f-bec5-42be-bd6b-866808179312" xlink:to="loc_us-gaap_SharesIssued_3e3a9fef-2c16-47ac-a63a-5209d96f51f1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_f3109be6-1211-413f-adb4-ea53695f4e5e" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_e39fcc0f-bec5-42be-bd6b-866808179312" xlink:to="loc_us-gaap_StockholdersEquity_f3109be6-1211-413f-adb4-ea53695f4e5e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_109fb297-7459-4c96-b9ac-9d7b86f3887c" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_TreasuryStockValueAcquiredCostMethod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_e39fcc0f-bec5-42be-bd6b-866808179312" xlink:to="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_109fb297-7459-4c96-b9ac-9d7b86f3887c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensationGross_c8e517eb-4647-445b-a790-d79c74a1bca8" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StockIssuedDuringPeriodValueShareBasedCompensationGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_e39fcc0f-bec5-42be-bd6b-866808179312" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensationGross_c8e517eb-4647-445b-a790-d79c74a1bca8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_5f3ae0fc-e1e3-4d78-a5d5-bab57ab69e63" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_e39fcc0f-bec5-42be-bd6b-866808179312" xlink:to="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_5f3ae0fc-e1e3-4d78-a5d5-bab57ab69e63" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityOther_2db0b63c-e35e-421e-8f4f-7ada770e05ab" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StockholdersEquityOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_e39fcc0f-bec5-42be-bd6b-866808179312" xlink:to="loc_us-gaap_StockholdersEquityOther_2db0b63c-e35e-421e-8f4f-7ada770e05ab" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsCommonStockCash_e99f4cf2-1725-477a-930f-48550a4a4eef" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DividendsCommonStockCash"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_e39fcc0f-bec5-42be-bd6b-866808179312" xlink:to="loc_us-gaap_DividendsCommonStockCash_e99f4cf2-1725-477a-930f-48550a4a4eef" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_e030212e-fde2-4edc-9571-32c21ba570a2" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_e39fcc0f-bec5-42be-bd6b-866808179312" xlink:to="loc_us-gaap_NetIncomeLoss_e030212e-fde2-4edc-9571-32c21ba570a2" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_5da2c581-6ad6-4d99-ab3e-cbf2c43def8e" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StockholdersEquity"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharesIssued_eef0ef6c-f5e4-46f8-9857-b4305685f599" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SharesIssued"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.insperity.com/role/AccountingPoliciesDetails" xlink:type="simple" xlink:href="nsp-20240331.xsd#AccountingPoliciesDetails"/>
  <link:definitionLink xlink:role="http://www.insperity.com/role/AccountingPoliciesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueLineItems_90e48719-9476-4f80-a8c3-1f4a8521f6bf" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DisaggregationOfRevenueLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueTable_4cd9aba2-c2f1-4c2a-a63b-4ce831a1af12" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DisaggregationOfRevenueTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_90e48719-9476-4f80-a8c3-1f4a8521f6bf" xlink:to="loc_us-gaap_DisaggregationOfRevenueTable_4cd9aba2-c2f1-4c2a-a63b-4ce831a1af12" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_986cc9c2-c688-451c-ba28-7fb024e01132" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_4cd9aba2-c2f1-4c2a-a63b-4ce831a1af12" xlink:to="loc_srt_StatementGeographicalAxis_986cc9c2-c688-451c-ba28-7fb024e01132" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_986cc9c2-c688-451c-ba28-7fb024e01132_default" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_986cc9c2-c688-451c-ba28-7fb024e01132" xlink:to="loc_srt_SegmentGeographicalDomain_986cc9c2-c688-451c-ba28-7fb024e01132_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_66988d33-10f9-40e1-a1b3-1b39a7dae172" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_986cc9c2-c688-451c-ba28-7fb024e01132" xlink:to="loc_srt_SegmentGeographicalDomain_66988d33-10f9-40e1-a1b3-1b39a7dae172" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_nsp_NortheastMember_ff54066b-36d1-4c08-9c61-c3ad6cbca2b4" xlink:href="nsp-20240331.xsd#nsp_NortheastMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_66988d33-10f9-40e1-a1b3-1b39a7dae172" xlink:to="loc_nsp_NortheastMember_ff54066b-36d1-4c08-9c61-c3ad6cbca2b4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_nsp_SoutheastMember_758d1433-3860-426f-8e75-8473ddbcb299" xlink:href="nsp-20240331.xsd#nsp_SoutheastMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_66988d33-10f9-40e1-a1b3-1b39a7dae172" xlink:to="loc_nsp_SoutheastMember_758d1433-3860-426f-8e75-8473ddbcb299" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_nsp_CentralMember_8331c77c-4406-440e-a877-3a657445eaa5" xlink:href="nsp-20240331.xsd#nsp_CentralMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_66988d33-10f9-40e1-a1b3-1b39a7dae172" xlink:to="loc_nsp_CentralMember_8331c77c-4406-440e-a877-3a657445eaa5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_nsp_SouthwestMember_fb0c28a3-5630-4fc8-b5d2-c76e133d9389" xlink:href="nsp-20240331.xsd#nsp_SouthwestMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_66988d33-10f9-40e1-a1b3-1b39a7dae172" xlink:to="loc_nsp_SouthwestMember_fb0c28a3-5630-4fc8-b5d2-c76e133d9389" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_nsp_WestMember_7ca75e8e-29ca-469d-8079-6c3ee10447a2" xlink:href="nsp-20240331.xsd#nsp_WestMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_66988d33-10f9-40e1-a1b3-1b39a7dae172" xlink:to="loc_nsp_WestMember_7ca75e8e-29ca-469d-8079-6c3ee10447a2" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_nsp_OtherRevenuesMember_04423fa7-555b-43d2-a1e2-13da5ce265fb" xlink:href="nsp-20240331.xsd#nsp_OtherRevenuesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_66988d33-10f9-40e1-a1b3-1b39a7dae172" xlink:to="loc_nsp_OtherRevenuesMember_04423fa7-555b-43d2-a1e2-13da5ce265fb" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_09bd0c3e-0982-4b7e-9ef0-6f744f6abb56" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_90e48719-9476-4f80-a8c3-1f4a8521f6bf" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_09bd0c3e-0982-4b7e-9ef0-6f744f6abb56" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.insperity.com/role/OtherBalanceSheetInformationDetails" xlink:type="simple" xlink:href="nsp-20240331.xsd#OtherBalanceSheetInformationDetails"/>
  <link:definitionLink xlink:role="http://www.insperity.com/role/OtherBalanceSheetInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsLineItems_10743c39-2056-453d-b8d2-8de350653e95" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CashAndCashEquivalentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfCashAndCashEquivalentsTable_9d412070-c6f9-4f7e-ac0f-b997caf28e11" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfCashAndCashEquivalentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_CashAndCashEquivalentsLineItems_10743c39-2056-453d-b8d2-8de350653e95" xlink:to="loc_us-gaap_ScheduleOfCashAndCashEquivalentsTable_9d412070-c6f9-4f7e-ac0f-b997caf28e11" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsAxis_bde47c63-19c6-4bef-ade1-afe434a75de4" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CashAndCashEquivalentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfCashAndCashEquivalentsTable_9d412070-c6f9-4f7e-ac0f-b997caf28e11" xlink:to="loc_us-gaap_CashAndCashEquivalentsAxis_bde47c63-19c6-4bef-ade1-afe434a75de4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_bde47c63-19c6-4bef-ade1-afe434a75de4_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CashAndCashEquivalentsAxis_bde47c63-19c6-4bef-ade1-afe434a75de4" xlink:to="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_bde47c63-19c6-4bef-ade1-afe434a75de4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_9980d941-aca9-48a4-bd40-91359e2f0936" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CashAndCashEquivalentsAxis_bde47c63-19c6-4bef-ade1-afe434a75de4" xlink:to="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_9980d941-aca9-48a4-bd40-91359e2f0936" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MoneyMarketFundsMember_99fd0b77-5ba0-4c54-bfd0-0b4b5fa64326" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_MoneyMarketFundsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_9980d941-aca9-48a4-bd40-91359e2f0936" xlink:to="loc_us-gaap_MoneyMarketFundsMember_99fd0b77-5ba0-4c54-bfd0-0b4b5fa64326" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsMember_aa52ee7e-7211-4387-8aeb-4d468a7e0bea" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CashAndCashEquivalentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_9980d941-aca9-48a4-bd40-91359e2f0936" xlink:to="loc_us-gaap_CashAndCashEquivalentsMember_aa52ee7e-7211-4387-8aeb-4d468a7e0bea" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_nsp_MoneyMarketFundsOvernightHoldingsAtCarryingValue_e9d9485e-2182-485e-8181-ad6209085e23" xlink:href="nsp-20240331.xsd#nsp_MoneyMarketFundsOvernightHoldingsAtCarryingValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CashAndCashEquivalentsLineItems_10743c39-2056-453d-b8d2-8de350653e95" xlink:to="loc_nsp_MoneyMarketFundsOvernightHoldingsAtCarryingValue_e9d9485e-2182-485e-8181-ad6209085e23" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShortTermInvestments_c9107ff2-dd76-457b-b251-04bb5859a8f5" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShortTermInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CashAndCashEquivalentsLineItems_10743c39-2056-453d-b8d2-8de350653e95" xlink:to="loc_us-gaap_ShortTermInvestments_c9107ff2-dd76-457b-b251-04bb5859a8f5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Cash_18f2d1f6-18a5-46c8-ae56-628268cfc587" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_Cash"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CashAndCashEquivalentsLineItems_10743c39-2056-453d-b8d2-8de350653e95" xlink:to="loc_us-gaap_Cash_18f2d1f6-18a5-46c8-ae56-628268cfc587" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_DraftsPayable_d52639f0-4d5a-44f0-a65c-79f00fd86e84" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_DraftsPayable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CashAndCashEquivalentsLineItems_10743c39-2056-453d-b8d2-8de350653e95" xlink:to="loc_srt_DraftsPayable_d52639f0-4d5a-44f0-a65c-79f00fd86e84" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCashEquivalentsAndShortTermInvestments_d2a0c76c-4036-481e-b28c-d18f34417e39" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CashCashEquivalentsAndShortTermInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CashAndCashEquivalentsLineItems_10743c39-2056-453d-b8d2-8de350653e95" xlink:to="loc_us-gaap_CashCashEquivalentsAndShortTermInvestments_d2a0c76c-4036-481e-b28c-d18f34417e39" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_nsp_PayrollWithholdingsIncludedInCashBalance_09b88c22-9b78-4ac8-84b2-7c9d2311d54e" xlink:href="nsp-20240331.xsd#nsp_PayrollWithholdingsIncludedInCashBalance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CashAndCashEquivalentsLineItems_10743c39-2056-453d-b8d2-8de350653e95" xlink:to="loc_nsp_PayrollWithholdingsIncludedInCashBalance_09b88c22-9b78-4ac8-84b2-7c9d2311d54e" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_nsp_ClientPrepaymentsIncludedInCashBalance_b85c077d-238f-486a-9b2d-7055371cdd2a" xlink:href="nsp-20240331.xsd#nsp_ClientPrepaymentsIncludedInCashBalance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CashAndCashEquivalentsLineItems_10743c39-2056-453d-b8d2-8de350653e95" xlink:to="loc_nsp_ClientPrepaymentsIncludedInCashBalance_b85c077d-238f-486a-9b2d-7055371cdd2a" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_67a9ecfc-067d-4629-8f17-a88275280d51" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CashAndCashEquivalentsLineItems_10743c39-2056-453d-b8d2-8de350653e95" xlink:to="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_67a9ecfc-067d-4629-8f17-a88275280d51" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue_dde0634e-642c-4f55-b7d8-65a78d88aed3" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CashAndCashEquivalentsLineItems_10743c39-2056-453d-b8d2-8de350653e95" xlink:to="loc_us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue_dde0634e-642c-4f55-b7d8-65a78d88aed3" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FundsHeldForClients_e1f38979-a9e0-4904-a8a5-199002edeff0" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FundsHeldForClients"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CashAndCashEquivalentsLineItems_10743c39-2056-453d-b8d2-8de350653e95" xlink:to="loc_us-gaap_FundsHeldForClients_e1f38979-a9e0-4904-a8a5-199002edeff0" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_nsp_DepositsWorkersCompensation_48079f56-f1b0-40a3-b0e5-877f9c40798e" xlink:href="nsp-20240331.xsd#nsp_DepositsWorkersCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CashAndCashEquivalentsLineItems_10743c39-2056-453d-b8d2-8de350653e95" xlink:to="loc_nsp_DepositsWorkersCompensation_48079f56-f1b0-40a3-b0e5-877f9c40798e" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_ea514dd0-6eaa-4d50-b46e-42e4306f08bf" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CashAndCashEquivalentsLineItems_10743c39-2056-453d-b8d2-8de350653e95" xlink:to="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_ea514dd0-6eaa-4d50-b46e-42e4306f08bf" xlink:type="arc" order="11"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.insperity.com/role/FairValueMeasurementsFairValueMeasurementsDetails" xlink:type="simple" xlink:href="nsp-20240331.xsd#FairValueMeasurementsFairValueMeasurementsDetails"/>
  <link:definitionLink xlink:role="http://www.insperity.com/role/FairValueMeasurementsFairValueMeasurementsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_ff7d26c8-5f11-4ea5-965c-795215e5e67d" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_dcbcba7b-5430-42f9-966d-12e570f36e12" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_ff7d26c8-5f11-4ea5-965c-795215e5e67d" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_dcbcba7b-5430-42f9-966d-12e570f36e12" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_4b2f089e-85fb-423d-9656-aa56bddc0de5" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_dcbcba7b-5430-42f9-966d-12e570f36e12" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_4b2f089e-85fb-423d-9656-aa56bddc0de5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_4b2f089e-85fb-423d-9656-aa56bddc0de5_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_4b2f089e-85fb-423d-9656-aa56bddc0de5" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_4b2f089e-85fb-423d-9656-aa56bddc0de5_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_7bc78ce5-a23e-402e-a661-b8a807f748c6" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_4b2f089e-85fb-423d-9656-aa56bddc0de5" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_7bc78ce5-a23e-402e-a661-b8a807f748c6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel12And3Member_bec3d121-3801-4938-a497-f7dbc716eb3d" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueInputsLevel12And3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_7bc78ce5-a23e-402e-a661-b8a807f748c6" xlink:to="loc_us-gaap_FairValueInputsLevel12And3Member_bec3d121-3801-4938-a497-f7dbc716eb3d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel1Member_d58215d0-3f3e-4151-b2f5-022a725d63a5" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueInputsLevel1Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueInputsLevel12And3Member_bec3d121-3801-4938-a497-f7dbc716eb3d" xlink:to="loc_us-gaap_FairValueInputsLevel1Member_d58215d0-3f3e-4151-b2f5-022a725d63a5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_66891beb-4d16-4242-ad11-b6d029d4262a" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueInputsLevel2Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueInputsLevel12And3Member_bec3d121-3801-4938-a497-f7dbc716eb3d" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_66891beb-4d16-4242-ad11-b6d029d4262a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_597e8642-7ea3-4391-852f-b5dd0b080468" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_dcbcba7b-5430-42f9-966d-12e570f36e12" xlink:to="loc_us-gaap_FinancialInstrumentAxis_597e8642-7ea3-4391-852f-b5dd0b080468" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_597e8642-7ea3-4391-852f-b5dd0b080468_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_597e8642-7ea3-4391-852f-b5dd0b080468" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_597e8642-7ea3-4391-852f-b5dd0b080468_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_98af8517-e9ea-4a4a-9a7e-bc52fe4996c1" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_597e8642-7ea3-4391-852f-b5dd0b080468" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_98af8517-e9ea-4a4a-9a7e-bc52fe4996c1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USTreasurySecuritiesMember_f18992cf-f6b4-410c-824e-e89f1df85db7" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_USTreasurySecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_98af8517-e9ea-4a4a-9a7e-bc52fe4996c1" xlink:to="loc_us-gaap_USTreasurySecuritiesMember_f18992cf-f6b4-410c-824e-e89f1df85db7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure_6e09a98d-07da-4b56-8365-c960c24d75a5" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CashAndCashEquivalentsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_ff7d26c8-5f11-4ea5-965c-795215e5e67d" xlink:to="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure_6e09a98d-07da-4b56-8365-c960c24d75a5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USGovernmentSecuritiesAtCarryingValue_2d16bf54-a281-4d9c-b247-da4eaed71db6" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_USGovernmentSecuritiesAtCarryingValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_ff7d26c8-5f11-4ea5-965c-795215e5e67d" xlink:to="loc_us-gaap_USGovernmentSecuritiesAtCarryingValue_2d16bf54-a281-4d9c-b247-da4eaed71db6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCashEquivalentsAtCarryingValue_fe563279-b7b9-4b58-8fe4-dbdd21a5211e" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherCashEquivalentsAtCarryingValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_ff7d26c8-5f11-4ea5-965c-795215e5e67d" xlink:to="loc_us-gaap_OtherCashEquivalentsAtCarryingValue_fe563279-b7b9-4b58-8fe4-dbdd21a5211e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosure_797a9000-d3df-4914-81c1-c922ac6b56e4" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AssetsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_ff7d26c8-5f11-4ea5-965c-795215e5e67d" xlink:to="loc_us-gaap_AssetsFairValueDisclosure_797a9000-d3df-4914-81c1-c922ac6b56e4" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_5e987781-3d04-4b8a-a1b6-4b3dd1038eb6" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_ff7d26c8-5f11-4ea5-965c-795215e5e67d" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_5e987781-3d04-4b8a-a1b6-4b3dd1038eb6" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_5ba2865a-80d5-4574-9386-69217c02cbf4" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_ff7d26c8-5f11-4ea5-965c-795215e5e67d" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_5ba2865a-80d5-4574-9386-69217c02cbf4" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_d7cf1adc-6087-4add-b528-06c8074bb860" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_ff7d26c8-5f11-4ea5-965c-795215e5e67d" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_d7cf1adc-6087-4add-b528-06c8074bb860" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtSecurities_658aa488-ef76-458f-9a2c-004bf9d3534d" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AvailableForSaleSecuritiesDebtSecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_ff7d26c8-5f11-4ea5-965c-795215e5e67d" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtSecurities_658aa488-ef76-458f-9a2c-004bf9d3534d" xlink:type="arc" order="7"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.insperity.com/role/LongtermDebtDetails" xlink:type="simple" xlink:href="nsp-20240331.xsd#LongtermDebtDetails"/>
  <link:definitionLink xlink:role="http://www.insperity.com/role/LongtermDebtDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityLineItems_90ab0ca6-8443-431d-8e2c-793df800043e" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LineOfCreditFacilityLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityTable_3e04c70d-d120-42f4-aa22-0b1fe2047846" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LineOfCreditFacilityTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_90ab0ca6-8443-431d-8e2c-793df800043e" xlink:to="loc_us-gaap_LineOfCreditFacilityTable_3e04c70d-d120-42f4-aa22-0b1fe2047846" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_14b0110b-1563-4045-8b81-7cf3fd1ecb81" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LineOfCreditFacilityTable_3e04c70d-d120-42f4-aa22-0b1fe2047846" xlink:to="loc_us-gaap_CreditFacilityAxis_14b0110b-1563-4045-8b81-7cf3fd1ecb81" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_14b0110b-1563-4045-8b81-7cf3fd1ecb81_default" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_14b0110b-1563-4045-8b81-7cf3fd1ecb81" xlink:to="loc_us-gaap_CreditFacilityDomain_14b0110b-1563-4045-8b81-7cf3fd1ecb81_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_7f8bd051-c162-4664-8c26-3583bf0e06a3" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_14b0110b-1563-4045-8b81-7cf3fd1ecb81" xlink:to="loc_us-gaap_CreditFacilityDomain_7f8bd051-c162-4664-8c26-3583bf0e06a3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BaseRateMember_a294cc0f-353a-438f-9b81-e4c7e1c41c75" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_BaseRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_7f8bd051-c162-4664-8c26-3583bf0e06a3" xlink:to="loc_us-gaap_BaseRateMember_a294cc0f-353a-438f-9b81-e4c7e1c41c75" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuredOvernightFinancingRateSofrOvernightIndexSwapRateMember_47dae258-417e-4ced-a3ba-ab06e191c089" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SecuredOvernightFinancingRateSofrOvernightIndexSwapRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_7f8bd051-c162-4664-8c26-3583bf0e06a3" xlink:to="loc_us-gaap_SecuredOvernightFinancingRateSofrOvernightIndexSwapRateMember_47dae258-417e-4ced-a3ba-ab06e191c089" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_6084208d-9af6-4771-b080-ec9a57d84831" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LineOfCreditFacilityTable_3e04c70d-d120-42f4-aa22-0b1fe2047846" xlink:to="loc_srt_RangeAxis_6084208d-9af6-4771-b080-ec9a57d84831" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_6084208d-9af6-4771-b080-ec9a57d84831_default" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_6084208d-9af6-4771-b080-ec9a57d84831" xlink:to="loc_srt_RangeMember_6084208d-9af6-4771-b080-ec9a57d84831_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_712a29a3-9947-49a7-9e2d-c4b77d5fe97a" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_6084208d-9af6-4771-b080-ec9a57d84831" xlink:to="loc_srt_RangeMember_712a29a3-9947-49a7-9e2d-c4b77d5fe97a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_ec582b6a-9ef0-491f-8a41-73ea1fdf3ebb" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_712a29a3-9947-49a7-9e2d-c4b77d5fe97a" xlink:to="loc_srt_MinimumMember_ec582b6a-9ef0-491f-8a41-73ea1fdf3ebb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_5009aa51-04d8-45da-8308-23af12624191" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_712a29a3-9947-49a7-9e2d-c4b77d5fe97a" xlink:to="loc_srt_MaximumMember_5009aa51-04d8-45da-8308-23af12624191" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity_98ef3077-3c5b-4421-bf2e-31c7b6607182" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_90ab0ca6-8443-431d-8e2c-793df800043e" xlink:to="loc_us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity_98ef3077-3c5b-4421-bf2e-31c7b6607182" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_35dadcb4-bd58-4d6f-bbf4-edf3c7e6b743" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_90ab0ca6-8443-431d-8e2c-793df800043e" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_35dadcb4-bd58-4d6f-bbf4-edf3c7e6b743" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_nsp_PercentageOfSubsidiaryStockSecuringDebt_279feab4-13a6-4da3-87f9-3c326fd508cd" xlink:href="nsp-20240331.xsd#nsp_PercentageOfSubsidiaryStockSecuringDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_90ab0ca6-8443-431d-8e2c-793df800043e" xlink:to="loc_nsp_PercentageOfSubsidiaryStockSecuringDebt_279feab4-13a6-4da3-87f9-3c326fd508cd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtNoncurrent_b4e7b7b1-6919-4b22-b981-9d3116f09d3a" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LongTermDebtNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_90ab0ca6-8443-431d-8e2c-793df800043e" xlink:to="loc_us-gaap_LongTermDebtNoncurrent_b4e7b7b1-6919-4b22-b981-9d3116f09d3a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LettersOfCreditOutstandingAmount_a5fe28e8-240e-4c23-96c6-da906ca1435a" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LettersOfCreditOutstandingAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_90ab0ca6-8443-431d-8e2c-793df800043e" xlink:to="loc_us-gaap_LettersOfCreditOutstandingAmount_a5fe28e8-240e-4c23-96c6-da906ca1435a" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity_f5ac3cfb-1682-44dd-b9ae-ebb39913711e" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_90ab0ca6-8443-431d-8e2c-793df800043e" xlink:to="loc_us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity_f5ac3cfb-1682-44dd-b9ae-ebb39913711e" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtMaturityDate_3ce11ab3-ff20-4680-a3ab-220485a39fb6" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LongTermDebtMaturityDate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_90ab0ca6-8443-431d-8e2c-793df800043e" xlink:to="loc_us-gaap_LongTermDebtMaturityDate_3ce11ab3-ff20-4680-a3ab-220485a39fb6" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_ab73b9ce-0a3d-4740-9fa1-0070044210e7" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtInstrumentBasisSpreadOnVariableRate1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_90ab0ca6-8443-431d-8e2c-793df800043e" xlink:to="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_ab73b9ce-0a3d-4740-9fa1-0070044210e7" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_nsp_ApplicableMarginFederalFundsRate_1c6e9a73-bb3b-4a10-bb09-9481ef511f8d" xlink:href="nsp-20240331.xsd#nsp_ApplicableMarginFederalFundsRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_90ab0ca6-8443-431d-8e2c-793df800043e" xlink:to="loc_nsp_ApplicableMarginFederalFundsRate_1c6e9a73-bb3b-4a10-bb09-9481ef511f8d" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_nsp_AdjustedTermSOFRRatePlusApplicableMargin_6db31325-f678-46d8-9e40-0ae586100647" xlink:href="nsp-20240331.xsd#nsp_AdjustedTermSOFRRatePlusApplicableMargin"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_90ab0ca6-8443-431d-8e2c-793df800043e" xlink:to="loc_nsp_AdjustedTermSOFRRatePlusApplicableMargin_6db31325-f678-46d8-9e40-0ae586100647" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_nsp_AdjustedTermSOFRRate_d6ef4d59-6a0f-4e7a-9a39-c3f59d1b4577" xlink:href="nsp-20240331.xsd#nsp_AdjustedTermSOFRRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_90ab0ca6-8443-431d-8e2c-793df800043e" xlink:to="loc_nsp_AdjustedTermSOFRRate_d6ef4d59-6a0f-4e7a-9a39-c3f59d1b4577" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage_a47c7745-a846-4ea2-a7c0-0789a3413399" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_90ab0ca6-8443-431d-8e2c-793df800043e" xlink:to="loc_us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage_a47c7745-a846-4ea2-a7c0-0789a3413399" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityInterestRateDuringPeriod_b9d60c36-881d-4578-90d0-dd2996c06185" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LineOfCreditFacilityInterestRateDuringPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_90ab0ca6-8443-431d-8e2c-793df800043e" xlink:to="loc_us-gaap_LineOfCreditFacilityInterestRateDuringPeriod_b9d60c36-881d-4578-90d0-dd2996c06185" xlink:type="arc" order="12"/>
  </link:definitionLink>
</link:linkbase>
