English

Alternative forms

• (Karnataka, Tamil Nadu) co-sister

Noun

co-sister-in-law ‎(plural co-sisters-in-law)

1. One's husband's brother's wife; or more generally one's spouse's sister-in-law, the sister of one spouse in relation to the siblings of the other spouse.
   1. (in the plural) The relationship between women who marry brothers
   • 1979, Paul Friedrich, editor, Language, Context, and the Imagination, page 193:

     [The Russian word] Yátrov', for the husband's brother's wife or co-sister-in-law, so diagnostic a status within the patrilocal household, has passed entirely out of the language.

   • 2006, Kalipatnam Rama Rao, C.L.L. Jayaprada (trans.), Yagnam and Other Stories, page 61:

     At first the wench's second co-sister-in-law and the middle sister-in-law got into it.

2. One's brother-in-law or sister-in-law's sister; that is, one's sibling's spouse's sister (one's sister's husband's sister or one's brother's wife's sister).
   1. (in the plural) The relationship between women whose brother and sister are married to each other

Usage notes

Generally used in translation, or in countries such as India (Andhra Pradesh) where the local language makes the distinction. In common speech in traditionally English-speaking countries, sister-in-law may be used.

The primary usage is for one's husband's brother's wife.

Synonyms

• (secondary sense): co-aunt (in relation to a common niece or nephew)

Coordinate terms

• co-sibling-in-law
• co-brother-in-law

Related terms

• co-in-law
• co-mother-in-law
• co-wife

Translations

Languages which have words for this relationship which are distinct from the word for sister-in-law. Not all are attested to have the second meaning above, though this may sometimes be an oversight: