A female sibling sharing a single parent.

Alternative spelling of half sister

A sibling's older sister (used especially by children or by parents in speaking to their children).

Synonym of younger sister

A woman who is simultaneously sister and wife to her husband. / In a polygamous marriage, a woman who is simultaneously the sister and co-wife of another. / A co-wife in general.

(genetics) Either of the two chromatids of a replicated chromosome.

A foreign city with which a city has a declared relationship of cordiality.

(nautical) A ship built to the same design and dimensions as another or belongs to the same owners as another.

plural of half sister

(business) A company that shares its parent company with another company. / (nonstandard) A subsidiary.