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Webster 1913 Edition


Sister-in-law

Sis′ter-in-lawˊ

,
Noun.
;
pl.
Sisters-in-law
.
The sister of one’s husband or wife; also, the wife of one's brother; sometimes, the wife of one's husband's or wife's brother.

Webster 1828 Edition


Sister-in-law

SISTER-IN-LAW

,
Noun.
A husband's or wife's sister.