Dictionary

brother–in–law

noun broth·er–in–law \ˈbrə-thər-ən-ˌlȯ, ˈbrəth-rən-, ˈbrə-thərn-\

: the brother of your husband or wife

: the husband of your sister

plural broth·ers–in–law \ˈbrə-thərz-ən-\

Full Definition of BROTHER-IN-LAW

: the brother of one's spouse

a : the husband of one's sister

b : the husband of one's spouse's sister

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14th century

BROTHERS-IN-LAW Defined for Kids

noun broth·er–in–law \ˈbrə-thər-ən-ˌlȯ\

plural broth·ers–in–law

: the brother of a person's husband or wife

: the husband of a person's sister

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