crap hat
noun
- vulgar slang (in the British army) a term used by paratroopers and commandos to refer to a soldier from a regiment in the rest of the army〈粗俚〉窝囊废, 蹩脚货（英国军队中伞兵和突击队员用于称呼其他兵团士兵的用语）。
词源
probably with derogatory reference to the standard khaki-coloured (now dark blue) berets, in contrast to the prized red and green berets of the special regiments.