Plural of adoption; multiple instances of legally taking a child to raise as one's own, or instances of accepting and putting something into use.
From Latin 'adoptio' (a choosing for oneself), plural form with '-s'. The word entered English from Old French and Latin, carrying both legal and metaphorical meanings.
Interestingly, 'adoption' applies to ideas and technologies too—we talk about 'technology adoption rates'—because both involve making something foreign into something truly yours, whether it's a child or an innovation.
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