wife-in-law
/ˌwaɪf ɪn ˈlɔː/noun
University
1
A wife in law only, such as one who has abandoned her husband
2
A wife who provides domestic or social support, but not love or affection
3
Another wife of one's husband. Typically used in cases of divorce and subsequent remarriage for one's husband's ex-wife, but sometimes used in polygamy for a co-wife.