noun · the wife of one's husband's paternal uncle (specifically the wife of his father's younger brother)

她是丈夫的亲叔母，按辈分我应当称呼她为叔婆。

noun · the wife of one's paternal grandfather's younger brother

叔婆是爷爷的弟媳，每年过年我们都要去她家拜年。