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

In your car, you should have a kit with a first aid kit, a blanket, a change of clothes, cash to buy gas, a spare tire and emergency food and water.

From Los Angeles Times • Feb. 7, 2023

While I was considering who to call for help, a woman with a sunny smile offered to assist me with changing the spare tire.

From Seattle Times • Jun. 19, 2022

He said the truck’s left front tire, which was a spare tire, blew out before impact.

From Washington Times • Mar. 18, 2022

The spare tire and jack were buried in the trunk under all our luggage, so everything had to be taken out before my father could even begin work on the tire.

From "Homesick" by Jean Fritz