sister-in-law
noun [ C ] uk/ˈsɪs.tə.rɪn.lɔː/ us/ˈsɪs.tɚ.ɪn.lɑː/ sisters-in-law
B2 嫂子；弟媳；大（或小）姑子；大（或小）姨子；妯娌；丈夫（或妻子）的嫂子（或弟媳）
the wife of your brother or sister, or the sister of your husband or wife, or the wife of the brother or sister of your husband or wife