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

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:019c71b4-fe60-717c-8704-61d52466d40a,g:07a26c64-5058-4356-bb87-457632faa0f8-->
<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.steris.com/role/CoverPageCoverPage" xlink:type="simple" xlink:href="ste-20260511.xsd#CoverPageCoverPage"/>
  <link:definitionLink xlink:role="http://www.steris.com/role/CoverPageCoverPage" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentInformationLineItems_019c71b4-fe60-759d-bcdf-048470a6af65" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_DocumentInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentInformationTable_019c71b4-fe60-77b4-9afe-198262f6d2df" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_DocumentInformationTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_dei_DocumentInformationLineItems_019c71b4-fe60-759d-bcdf-048470a6af65" xlink:to="loc_dei_DocumentInformationTable_019c71b4-fe60-77b4-9afe-198262f6d2df" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_019c71b4-fe60-78c0-86b5-033d404c7969" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_dei_DocumentInformationTable_019c71b4-fe60-77b4-9afe-198262f6d2df" xlink:to="loc_us-gaap_StatementClassOfStockAxis_019c71b4-fe60-78c0-86b5-033d404c7969" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_019c71b4-fe60-78c0-86b5-033d404c7969_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_019c71b4-fe60-78c0-86b5-033d404c7969" xlink:to="loc_us-gaap_ClassOfStockDomain_019c71b4-fe60-78c0-86b5-033d404c7969_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_019c71b4-fe60-77cb-8a9d-388bba52e19b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_019c71b4-fe60-78c0-86b5-033d404c7969" xlink:to="loc_us-gaap_ClassOfStockDomain_019c71b4-fe60-77cb-8a9d-388bba52e19b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_019c71b4-fe60-7fed-a2be-7a46241fb53e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019c71b4-fe60-77cb-8a9d-388bba52e19b" xlink:to="loc_us-gaap_CommonStockMember_019c71b4-fe60-7fed-a2be-7a46241fb53e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ste_STETwo700SeniorNotesDue2031MemberMember_019c71b4-fe60-7a6f-9075-1a9585f10a88" xlink:href="ste-20260511.xsd#ste_STETwo700SeniorNotesDue2031MemberMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019c71b4-fe60-77cb-8a9d-388bba52e19b" xlink:to="loc_ste_STETwo700SeniorNotesDue2031MemberMember_019c71b4-fe60-7a6f-9075-1a9585f10a88" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ste_Two700SeniorNotesDue2051MemberMember_019c71b4-fe60-7e22-b02c-a8ad69da76b6" xlink:href="ste-20260511.xsd#ste_Two700SeniorNotesDue2051MemberMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019c71b4-fe60-77cb-8a9d-388bba52e19b" xlink:to="loc_ste_Two700SeniorNotesDue2051MemberMember_019c71b4-fe60-7e22-b02c-a8ad69da76b6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentType_019c71b4-fe60-7a7a-86bf-68006782a5bf" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_DocumentType"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019c71b4-fe60-759d-bcdf-048470a6af65" xlink:to="loc_dei_DocumentType_019c71b4-fe60-7a7a-86bf-68006782a5bf" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentPeriodEndDate_019c71b4-fe60-7193-bcd9-99c1a60d4ce6" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_DocumentPeriodEndDate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019c71b4-fe60-759d-bcdf-048470a6af65" xlink:to="loc_dei_DocumentPeriodEndDate_019c71b4-fe60-7193-bcd9-99c1a60d4ce6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityRegistrantName_019c71b4-fe60-72f5-ace9-c9219c6da9d6" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityRegistrantName"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019c71b4-fe60-759d-bcdf-048470a6af65" xlink:to="loc_dei_EntityRegistrantName_019c71b4-fe60-72f5-ace9-c9219c6da9d6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityIncorporationStateCountryCode_019c71b4-fe60-77d3-bcef-0f6616dd957b" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityIncorporationStateCountryCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019c71b4-fe60-759d-bcdf-048470a6af65" xlink:to="loc_dei_EntityIncorporationStateCountryCode_019c71b4-fe60-77d3-bcef-0f6616dd957b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityFileNumber_019c71b4-fe60-720c-9ae9-5ee8e0328db7" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityFileNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019c71b4-fe60-759d-bcdf-048470a6af65" xlink:to="loc_dei_EntityFileNumber_019c71b4-fe60-720c-9ae9-5ee8e0328db7" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressAddressLine1_019c71b4-fe60-7a5c-b54a-c527efc94309" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityAddressAddressLine1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019c71b4-fe60-759d-bcdf-048470a6af65" xlink:to="loc_dei_EntityAddressAddressLine1_019c71b4-fe60-7a5c-b54a-c527efc94309" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressCityOrTown_019c71b4-fe60-7c44-bd5d-48c3cd96eb6b" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityAddressCityOrTown"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019c71b4-fe60-759d-bcdf-048470a6af65" xlink:to="loc_dei_EntityAddressCityOrTown_019c71b4-fe60-7c44-bd5d-48c3cd96eb6b" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressCountry_019c71b4-fe60-7a76-9b10-0c04a044f3a9" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityAddressCountry"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019c71b4-fe60-759d-bcdf-048470a6af65" xlink:to="loc_dei_EntityAddressCountry_019c71b4-fe60-7a76-9b10-0c04a044f3a9" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressPostalZipCode_019c71b4-fe60-7277-9da5-847d3f2f6fe9" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityAddressPostalZipCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019c71b4-fe60-759d-bcdf-048470a6af65" xlink:to="loc_dei_EntityAddressPostalZipCode_019c71b4-fe60-7277-9da5-847d3f2f6fe9" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_CityAreaCode_019c71b4-fe60-7c09-9b54-702ed630ec6b" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_CityAreaCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019c71b4-fe60-759d-bcdf-048470a6af65" xlink:to="loc_dei_CityAreaCode_019c71b4-fe60-7c09-9b54-702ed630ec6b" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LocalPhoneNumber_019c71b4-fe60-725f-ad84-bbbb3be96c50" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_LocalPhoneNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019c71b4-fe60-759d-bcdf-048470a6af65" xlink:to="loc_dei_LocalPhoneNumber_019c71b4-fe60-725f-ad84-bbbb3be96c50" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_WrittenCommunications_019c71b4-fe60-7059-a079-71a09924cab2" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_WrittenCommunications"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019c71b4-fe60-759d-bcdf-048470a6af65" xlink:to="loc_dei_WrittenCommunications_019c71b4-fe60-7059-a079-71a09924cab2" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SolicitingMaterial_019c71b4-fe60-7a06-a653-d4bc86dfb81d" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_SolicitingMaterial"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019c71b4-fe60-759d-bcdf-048470a6af65" xlink:to="loc_dei_SolicitingMaterial_019c71b4-fe60-7a06-a653-d4bc86dfb81d" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_PreCommencementIssuerTenderOffer_019c71b4-fe60-7d81-bb98-23b722023ef1" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_PreCommencementIssuerTenderOffer"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019c71b4-fe60-759d-bcdf-048470a6af65" xlink:to="loc_dei_PreCommencementIssuerTenderOffer_019c71b4-fe60-7d81-bb98-23b722023ef1" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_PreCommencementTenderOffer_019c71b4-fe60-7e62-af1c-f0a1c6aff4b7" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_PreCommencementTenderOffer"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019c71b4-fe60-759d-bcdf-048470a6af65" xlink:to="loc_dei_PreCommencementTenderOffer_019c71b4-fe60-7e62-af1c-f0a1c6aff4b7" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_Security12bTitle_019c71b4-fe60-733a-a19b-a80c99c92e52" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_Security12bTitle"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019c71b4-fe60-759d-bcdf-048470a6af65" xlink:to="loc_dei_Security12bTitle_019c71b4-fe60-733a-a19b-a80c99c92e52" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_TradingSymbol_019c71b4-fe60-7be2-8af5-9cd7857082b3" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_TradingSymbol"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019c71b4-fe60-759d-bcdf-048470a6af65" xlink:to="loc_dei_TradingSymbol_019c71b4-fe60-7be2-8af5-9cd7857082b3" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SecurityExchangeName_019c71b4-fe60-7542-9957-c27a1398aa78" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_SecurityExchangeName"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019c71b4-fe60-759d-bcdf-048470a6af65" xlink:to="loc_dei_SecurityExchangeName_019c71b4-fe60-7542-9957-c27a1398aa78" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityEmergingGrowthCompany_019c71b4-fe60-71ec-bb31-1e106d11e604" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityEmergingGrowthCompany"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019c71b4-fe60-759d-bcdf-048470a6af65" xlink:to="loc_dei_EntityEmergingGrowthCompany_019c71b4-fe60-71ec-bb31-1e106d11e604" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_AmendmentFlag_019c71b4-fe60-7f6b-b6eb-5d4b7ac93677" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_AmendmentFlag"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019c71b4-fe60-759d-bcdf-048470a6af65" xlink:to="loc_dei_AmendmentFlag_019c71b4-fe60-7f6b-b6eb-5d4b7ac93677" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityCentralIndexKey_019c71b4-fe60-7c3d-b985-c4409e10fa55" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityCentralIndexKey"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019c71b4-fe60-759d-bcdf-048470a6af65" xlink:to="loc_dei_EntityCentralIndexKey_019c71b4-fe60-7c3d-b985-c4409e10fa55" xlink:type="arc" order="20"/>
  </link:definitionLink>
</link:linkbase>
