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Glite Dictionary
swim bladder

swim bladder

1 5.0
An air sac in many fish that helps them stay at a certain depth in water
  • noun
  • /swɪm ˈblædər/
  • Specialized
: vejiga natatoria
  • By using the muscles surrounding the swim bladder, these fish can produce a drumming sound—hence the name.
  • swim bladder expansion

They don't have swim bladders like the Bony fishes do.

Examples

  • Assuming unrestricted expansion, a fish brought from 65 m may experience a 7.5-fold increase in gas volume in its swim bladder.

    Academic text (1992)

  • The problems are more serious for fish caught at greater depths, especially for physoclistous fishes with closed swim bladders.

    Academic text (1992)

  • In most living fish, however, lungs have transformed into swim bladders.

    Academic text (2003)

  • Can sense the swim bladders that fish use to maintain their buoyancy.

  • Lingcod lack a swim bladder and apparently do not suffer adverse gas expansion effects.

    Academic text (1998)

  • Both the swim bladder and lateral line system are well developed, especially in the sciaenids.

    Academic text (1995)

  • Swim bladder problems and constipation are among the leading causes of death in goldfish.

    Blog text (20)

  • Slimy sculpin lack swim bladders and are relatively poor swimmers (Scott and Crossman 1973).

    Academic text (1999)

  • The male toadfish guard their nests, and during the night they use muscles around their swim bladders to vibrate them, creating a call to lure in females.

  • Many fish have a swim bladder, a gas-filled sac that helps them maintain their buoyancy at different depths.

Synonyms

air bladder
vsswim bladder
  • Specialized
1 4.9

A sac inside many fish that holds air and helps them float at different depths

is the general name focusing on buoyancy control rather than location
float
vsswim bladder
  • Specialized
1 7.4

An air sac near a fish's backbone that helps it stay level in water

is framed generally about buoyancy instead of giving specific location

Surface Forms

swim bladder singular
swim bladders plural

Morphology

swim + bladder

The compound 'swim bladder' is directly interpretable as a bladder (an organ that stores gas) related to swimming; a B1 learner who knows 'swim' and 'bladder' can infer an air-filled organ used for buoyancy. This noun+noun compositional pattern is cross-linguistically common, so the meaning is immediately derivable from the constituents.

Etymology

Swim bladder is a compound name for a small, air-filled sac inside many fish. The bladder works like a tiny balloon the fish can fill or empty to help it swim at different depths, so the name explains why the organ lets a fish 'float' or 'stay at a particular depth' without much effort.