Flat tire

[Dave Paprocki]

a tire that does not have any or enough air in it

[Vania]

a deflated pneumatic tire

[Antoinegap]

A flat tire (British English: flat tyre) is a deflated pneumatic tire, which can cause the rim of the wheel to ride on the tire tread or the ground potentially resulting in loss of control of the vehicle or irreparable damage to the tire. The most common cause of a flat tire is puncturing of the tire by a sharp object, such as a nail or pin, letting the air escape. Depending on the size of the puncture, the tire may deflate slowly or rapidly.