air filter


Definition of air filter

: 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

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First Known Use of air filter

1841, in the meaning defined above

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The first known use of air filter was in 1841

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Cite this Entry

“Air filter.” Dictionary, Merriam-Webster, Accessed 5 Aug. 2020.

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