portcullis/ˌpɔ:tˈkʌlɪs; pɔrt`kʌlɪs/ n(formerly) strong heavy iron grating raised or lowered at the entrance to a castle （旧时）（城堡入口可升降的）铁闸门, 吊闸. =>illus at castle 见 castle 插图.
牛津英汉双解词典