Any of various devices for the filtration of water by physical, chemical, or biological means, to free it from suspended solids and other impurities, typically to render it fit for drinking.
Origin
Early 19th century.
Definition of water filter in US English:
water filter
noun
Any of various devices for the filtration of water by physical, chemical, or biological means, to free it from suspended solids and other impurities, typically to render it fit for drinking.