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sister-in-law

noun sis·ter-in-law \ ˈsi-st(ə-)rən-ˌlȯ , -tərn-ˌlȯ \
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plural sisters-in-law play \ˈsi-stər-zən-ˌlȯ\
1 : the sister of one's spouse
2 a : the wife of one's sibling
b : the wife of one's spouse's sibling

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First Known Use of sister-in-law

15th century

in the meaning defined at sense 1

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SISTER-IN-LAW Defined for English Language Learners

sister-in-law

noun

  • : the sister of your husband or wife

  • : the wife of your brother

SISTER-IN-LAW Defined for Kids

sister-in-law

noun sis·ter-in-law \ ˈsi-stər-ən-ˌlȯ \
plural sisters-in-law
1 : the sister of someone's husband or wife
2 : the wife of someone's brother

Learn More about sister-in-law

  1. See words that rhyme with sister-in-law Spanish Central: Translation of sister-in-law Nglish: Translation of sister-in-law for Spanish speakers Britannica English: Translation of sister-in-law for Arabic speakers

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