air filter

noun

: a filter that removes particles and impurities from the air: such as

a

: an apparatus designed to improve the quality of circulating air by filtering out impurities

Once the air is returned to the furnace fan, it is pulled through air filters to remove dust and dirt.

—James L. Kittle, Home Heating and Air Conditioning Systems, 1990

b

: an apparatus placed between the air intake and the engine of an automobile that removes impurities from the air before it is mixed with the fuel

On older carburetor-equipped vehicles, the air filter is located in the housing on top of the engine.

—Vyvyan Lynn and Tony Molla, The Complete Idiot's Guide to Auto Repair, 2007

Word History

First Known Use

1841, in the meaning defined above

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