air-bladder

A fish uses its air-bladder to control its buoyancy in the water.

Definition

Noun: - A gas-filled sac: An "air-bladder" is a membranous sac, typically found in certain fish and aquatic animals, that contains gas and functions primarily in buoyancy control and, in some species, in respiration or sound production.

Usage Examples

• (A gas-filled sac for buoyancy.)
• (A sac used for sensory functions.)

Advanced Usage

• "to inflate the air-bladder": to fill the sac with gas for buoyancy.

  • The fish rapidly inflates its air-bladder to rise to the surface. (Adjusts its gas volume to change depth.)

• "air-bladder rupture": damage or bursting of the sac, often fatal.

  • A sudden change in pressure can cause an air-bladder rupture in deep-sea fish. (Injury due to rapid ascent.)

Variants and Related Words

• Swim bladder (n): a synonym commonly used in ichthyology for the air-bladder in bony fish.

  • The swim bladder is homologous to the lungs of terrestrial vertebrates. (The same organ evolved for different functions.)

• Gas bladder (n): another term for the air-bladder, emphasizing its gas content.

  • The gas bladder secretes oxygen to maintain neutral buoyancy. (The organ's gas-secreting function.)

Synonyms

• Swim bladder: the standard term in biology for this organ in fish.
• Gas bladder: a technical synonym used in zoology.
• Hydrostatic organ: a broader term for any structure controlling buoyancy.

Related Idioms