antiknock

[ an-tee-nok, an-tahy-, an-tee-nok, an-tahy- ]

adjective

1. noting or pertaining to a substance, as tetraethyllead or ferrocene, used as a fuel additive for an internal-combustion engine to eliminate or minimize knock.

noun

1. such a substance added to fuel in an internal-combustion engine.

antiknock

/ ˌæntɪˈnɒk /

noun

1. a compound, such as lead tetraethyl, added to petrol to reduce knocking in the engine

Word History and Origins

Origin of antiknock¹

First recorded in 1920–25; anti- + knock

Example Sentences

Modern engines not only don’t need lead but have sophisticated antiknock technologies that sense a fuel’s octane rating and adjust their ignition timing to prevent damage.

From New York Times