air filter

noun

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. KittleHome Heating and Air Conditioning Systems1990
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 MollaThe Complete Idiot’s Guide to Auto Repair2007

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First Known Use of air filter

1841


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