Of a family relationship by marriage of a relative (or through affinity), as opposed to consanguinity; in-law.(adjective)
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Use "affinal" in a sentence
"Kin networks, endogamy, and repeated affinal marriages were evident by the second generation, establishing patterns that persisted throughout the eighteenth century."
"The settlers 'ability to make and sustain disparate claims depended on social relationships, so their decisions about when and where to claim land were predicated on both practical and affinal considerations."
"Since according to the norms of virilocal marriage, no married adult woman lives in the muti of her father's family (and indeed might live a long distance from her natal home), the creation of a namesake bond with a younger woman presents a way to strengthen existing ties of blood or affinal kinship, and to foster a lifelong relationship of mutual affection and assistance that will, necessarily, stretch across geographic space."