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

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

Each summer, thousands of people boat, kayak or float on inner tubes on the river, which boasts whitewater areas as well as trout and salmon fisheries.

From BBC

An 11-year-old girl has been rescued after clinging to inner tubes for three days in stormy weather in the Mediterranean.

From BBC

“Also, do not tie two or more inner tubes together; this requires you to have a life jacket for each person. Kids 12 and younger must wear a life jacket.”

From Los Angeles Times