Filter

Filter , noun

[French filtre, the same word as feutre felt, Late Latin filtrum, feltrum, felt, fulled wool, this being used for straining liquors. See Feuter.]

Any porous substance, as cloth, paper, sand, or charcoal, through which water or other liquid may passed to cleanse it from the solid or impure matter held in suspension; a chamber or device containing such substance; a strainer; also, a similar device for purifying air.

Collocations (2)

Filter bed , a pond, the bottom of which is a filter composed of sand gravel.

Filter gallery , an underground gallery or tunnel, alongside of a stream, to collect the water that filters through the intervening sand and gravel; -- called also infiltration gallery.

Filter , transitive verb

[Compare French filter. See Filter, n., and compare Filtrate.]

To purify or defecate, as water or other liquid, by causing it to pass through a filter.

Collocations (1)

Filtering paper or Filter paper , a porous unsized paper, for filtering.

Filter , intransitive verb

To pass through a filter; to percolate.

Filter , noun

Same as Philter.