An apparatus in which coal gas, hydrogen, or air is passed through or over a volatile hydrocarbon, in order to confer or increase illuminating power. [1913 Webster]
One that carburets; specif., an apparatus in which air or gas is carbureted, as by passing it through a light petroleum oil. The carburetor for a gasoline engine is usually either a surface carburetor, or alternatively a float carburetor (called also float-feed carburetor, or spray carburetor). In the former air is charged by being passed over the surface of gasoline. In the latter a fine spray of gasoline is drawn from an atomizing nozzle by a current of air induced by the suction of the engine piston, the supply of gasoline being regulated by a float which actuates a needle valve controlling the outlet of the feed pipe. Alcohol and other volatile inflammable liquids may be used instead of gasoline. [Webster 1913 Suppl.]

OXFORD DICTIONARY

carburettor, n. (also carburetter, US carburetor) an apparatus for carburation of petrol and air in an internal-combustion engine.

Etymology

as CARBURET + -OR(1)

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