a dark underground room used as a prison, especially in a castle （尤指城堡中的）地牢，土牢 Throw him into the dungeons! 把他扔进地牢！
Word OriginMiddle English (also with the sense ‘castle keep’): from Old French (perhaps originally with the sense ‘lord's tower’ or ‘mistress tower’), based on Latin dominus ‘lord, master’.