swim bladder

American  

noun

1. air bladder.

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swim bladder British  

noun

1. ichthyol another name for air bladder

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Etymology

Origin of swim bladder

First recorded in 1830–40

Example Sentences

Otophysan fish improved this pathway by adding small bony "ossicles" that connect the air bladder, often mistakenly called the swim bladder, to the inner ear.

From Science Daily • Nov. 3, 2025

The vaquitas are caught and drown in illegal gill nets set for Totoaba, a Gulf fish whose swim bladder is considered a prized delicacy in China, worth thousands of dollars per pound.

From Seattle Times • Aug. 30, 2023

The swim bladder, an organ that helps the fish stay afloat, is highly prized in China for its perceived - though unproven - medicinal properties.

From BBC • May 5, 2022

Their lungs evolved from their swim bladder — the internal pool float that helps them hold to a certain depth.

From New York Times • Feb. 10, 2021

It corresponds with the swim bladder of most modern fishes, and appears to have had a common origin with it.

From The Elements of Geology by Norton, William Harmon