air bladder

2 definitions found

air bladder - Collaborative International Dictionary of English v.0.48 :

  air bladder \air" blad`der\
     1. (Anat.) An air sac, sometimes double or variously lobed,
        in the visceral cavity of many fishes. It originates in
        the same way as the lungs of air-breathing vertebrates,
        and in the adult may retain a tubular connection with the
        pharynx or esophagus.
        [1913 Webster]
  
     2. A sac or bladder full of air in an animal or plant; also
        an air hole in a casting.
        [1913 Webster]

air bladder - WordNet (r) 2.1 (2005) :

  air bladder
      n 1: an air-filled sac near the spinal column in many fishes
           that helps maintain buoyancy [syn: air bladder, swim bladder
           , float]