Dictionary

sister–in–law

noun sis·ter–in–law \ˈsis-t(ə-)rən-ˌlȯ, -tərn-ˌlȯ\

: the sister of your husband or wife

: the wife of your brother

plural sis·ters–in–law \-tər-zən-\

Full Definition of SISTER-IN-LAW

: the sister of one's spouse

a : the wife of one's brother

b : the wife of one's spouse's brother

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15th century

SISTER-IN-LAW Defined for Kids

noun sis·ter–in–law \ˈsi-stər-ən-ˌlȯ\

plural sis·ters–in–law

: the sister of someone's husband or wife

: the wife of someone's brother

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