寒蝉,指寒天的蝉。仗马,指皇宫仪仗中的立马。寒蝉仗马形容闷不吭声、不敢说话。《官场现形记・序》:“明达之士岂故为寒蝉仗马哉?摄之于心,故慎之于口耳。”或作“仗马寒蝉”。
英语 as mute as a fish(as quiet as a mouse)