spare tire

American  

noun

1. a tire used or kept available as an emergency replacement on a vehicle.

2. Informal. excess fat around the waistline.

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spare tire Idioms  

1. Fat around one's middle, as in He's determined to lose ten pounds and that spare tire he's acquired. This expression transfers the term for an extra tire carried in cars in case of a flat tire to excess fat around the waist. [Colloquial; mid-1900s]

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Etymology

Origin of spare tire

First recorded in 1920–25

Example Sentences

No more flatbed, which Joe conceded was mostly pointless with the bulky spare tire filling it up.

From Slate • Jun. 22, 2025

The next morning, Sylvia finds him shivering and near-incoherent, sitting in a spare tire on the ground.

From New York Times • Jan. 4, 2024

Equipping a car with a spare tire increases the cost of building it.

From Los Angeles Times • Aug. 18, 2023

The National Highway Traffic Safety Administration says in documents posted Thursday that water can accumulate in the spare tire wheel well and damage the fuel pump control unit.

From Seattle Times • Jan. 5, 2023

The book that was the reason for their own journey was in the trunk, under the spare tire.

From "Inkheart" by Cornelia Funke