A chock is a wedge of wood or metal that you place behind a wheel to keep a vehicle from rolling. Mechanics often use a chock as a safety measure while they're working on a car.

Even if you've set the parking brake on your car, it's safer to also use a chock while you're working on it to ensure it doesn't move. There are special chocks for motorcycles, airplanes, and heavy trucks. You can also use chock as a verb, to mean "stop from rolling forward." The word's original meaning was "lumpy piece of wood," from Old North French choque, or "block."

Definitions of chock
  1. noun
    a block of wood used to prevent the sliding or rolling of a heavy object
    synonyms: wedge
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    a chock or bar wedged under a wheel or between the spokes to prevent a vehicle from rolling down an incline
    type of:
    a solid piece of something (usually having flat rectangular sides)
  2. verb
    secure with chocks
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    type of:
    fasten, fix, secure
    cause to be firmly attached
  3. verb
    support on chocks
    chock the boat”
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    type of:
    hold, hold up, support, sustain
    be the physical support of; carry the weight of
  4. adverb
    as completely as possible
    “it was chock-a-block full”
    synonyms: chock-a-block
Word Family

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