co-mother

名词noun

1. 1obsoleteThe relationship of a godmother to the other god-parents, and the legal parents, of a child.
2. 2In polygamy, a wife of one's father who is not one's mother; that is, co-wife of one's mother.
3. 3In polygamy, the relationship between one co-wife and another, in respect to their children.
4. 4In a lesbian couple, the nonbirth mother (partner of the birth mother