柯林斯詞典air bladder 1. N an air-filled sac, lying above the alimentary canal in bony fishes, that regulates buoyancy at different depths by a variation in the pressure of the air 魚(yú)鰾 (Also called swim bladder)[ichthyol] 返回 air bladder劍橋詞典a small bag of air or gas inside a fish's body , that helps it to float or breathe 魚(yú)鰾（幫助魚(yú)控制浮沉和呼吸） 返回 air bladder