Definition of Denver boot in US English:

Denver boot

noun

North American
  • see boot (sense 1 of the noun)
    • ‘Unlawfully parked cars are liable to be towed away or locked with Denver boots.’
    • ‘Greg was drunk, so the police put a Denver boot on his car.’
    • ‘On 15 September 1998, in LaSalle, Rosalind Burrowes was loudly objecting as bailiffs bolted a Denver boot on her wheel.’

Origin

1940s: named after Denver, Colorado, where the boot was introduced in 1949.

Pronunciation

Denver boot

/ˈdenvərbuːt/