A woman who raises an adopted child; an adoptive or foster mother (not the biological mother).
養母は子の教育に熱心だった。
The adoptive mother was devoted to the child's education.
養母と実母が面会する場面がドキュメンタリーで取り上げられた。
A meeting between the adoptive mother and the biological mother was featured in a documentary.
養母としての責任を果たすために、彼女は仕事を辞めた。
She quit her job to fulfill her responsibilities as an adoptive mother.