air bladder(redirected from air bladders)
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1. (Zoology) ichthyol Also called: swim bladder 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
2. (Botany) any air-filled sac, such as one of the bladders of seaweeds
1. a vesicle or sac containing air.
2. an air-filled sac at the top of the body cavity in bony fishes, serving in most to regulate hydrostatic pressure. Also called swim bladder.
An air-filled sac in many fish that helps maintain buoyancy or, in some species, helps in respiration, sound production, or hearing. Also called swim bladder. See float.