Longman Dictionary of Contemporary English
Wiktionary
n. A device, locked to the wheel of a motor car to prevent it from being driven; normally used to enforce payment of a traffic violation fine
Wikipedia
A wheel clamp, also known as wheel boot, parking boot, or Denver boot, is a device that is designed to prevent vehicles from being moved. In its most common form, it consists of a clamp that surrounds a vehicle wheel, designed to prevent removal of both itself and the wheel.
In the United States, the device became known as a "Denver boot" after the city of Denver, Colorado, which was the first in the country to employ them, mostly to force the payment of outstanding parking tickets.
Usage examples of "wheel clamp".
So, as an incentive and to ensure just reward, they had instituted a system which was, in its way, every bit as fundamentally brilliant and divinely inspired as had been the wheel clamp in twentieth-century London.