• Antiknock

    Alternative forms

    Origin

    - + knock

    Full definition of antiknock

    Adjective

    antiknock

    1. of an additive added to petroleum/gasoline to reduce the occurrence of engine knock.

    Noun

    antiknock

    (plural antiknocks)
    1. Such a substance, usually tetraethyl lead (also MMT, MTBE and ethanol)
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