sister-in-law
Meaning
the sister of one's husband or wife.
the wife of one's brother.
the wife of one's husband or wife's brother.
Structure
Usage
my sister-in-law is organizing a family reunion this summer.
he gets along very well with his brother's new wife, his sister-in-law.
after the wedding, i gained not just a husband but also a wonderful sister-in-law.
Etymology
the compound "sister-in-law" is a native english formation, built from core germanic vocabulary. the term "sister" originates from old english 'sweostor', sharing a proto-indo-european root with latin 'soror'. the component "in-law" emerged in middle english to denote kinship not by blood but by marriage, a concept solidified through canon and civil law. the phrase literally means "a sister by legal affiliation," where "law" extends from its concrete sense of a rule to signify the social contract of marriage. this construction efficiently distinguishes biological siblings from those acquired through marital alliances.
Analysis
sister (old english, meaning a female sibling); in (old english, a preposition indicating association or connection); law (old english, from old norse 'lag', meaning something laid down or fixed, here denoting a relationship established by custom or legal bond).