inner tube

American  

noun

1. a doughnut-shaped, flexible rubber tube inflated inside a tire to bear the weight of a vehicle.

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inner tube British  

noun

1. an inflatable rubber tube that fits inside a pneumatic tyre casing

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Etymology

Origin of inner tube

First recorded in 1890–95

Example Sentences

Teaser videos include depictions of babies on water skis and a runway model whose dress features an inner tube and giant cigarette butts.

From The Wall Street Journal • Jan. 5, 2026

Consider the analogy of trying to capture a 3D image of a child wearing an inner tube around their waist.

From Science Daily • Apr. 22, 2024

Glover said she and her husband, who was at the helm of the pontoon boat towing their son’s inner tube, saw Hubbard racing toward them.

From Los Angeles Times • Jul. 14, 2023

His mother and 10 others died while González, tied to an inner tube, drifted in open water until his rescue.

From Seattle Times • Jun. 29, 2023

I watch as the 4 friends get into the clover leaf-shaped inner tube.

From "The Miscalculations of Lightning Girl" by Stacy McAnulty