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English definition of “sister-in-law”


noun [C]     /ˈsɪs.tə.rɪn.lɔː/ US  /-tɚ.ɪn.lɑː/ (plural sisters-in-law)
B2 the wife of your brother or sister, or the sister of your husband or wife, or the wife of the brother or sister of your husband or wifeNon-blood relations
(Definition of sister-in-law noun from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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