Fil"ter (?), n. [F. filtre, the same word as feutre felt, LL. 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.
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.
© Webster 1913.
Fil"ter, v. t. [imp. & p. p. Filtered (?); p. pr. & vb. n. Filtering] [Cf. F. filter. See Filter, n., and cf. Filtrate.]
To purify or defecate, as water or other liquid, by causing it to pass through a filter.
Filtering paper, ∨ Filter paper, a porous unsized paper, for filtering.
© Webster 1913.
Fil"ter, v. i.
To pass through a filter; to percolate.
© Webster 1913.
Fil"ter, n.
Same as Philter.
© Webster 1913.