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

When it’s your turn, everyone gets into an oversize yellow inner tube, and you swish through an enclosed waterslide.

From The Wall Street Journal • Jan. 7, 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

Two years ago a 12-year-old boy on an inner tube was attacked but not seriously hurt by an otter on Montana’s Big Hole River.

From Seattle Times • Aug. 3, 2023

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

Taft and Will want me to take them tubing—drive the small motorboat while they float behind it in an inner tube.

From "We Were Liars" by E. Lockhart