Filter

n. [Fr. filtre, feutre, Sp. filtro, fieltro, It. filtro, feltro, L. Lat. filtrum, feltrum, properly felt, fulled wool, lana coacta, this being used for straining liquors. Cf. FEUTER.] A piece of woolen cloth, paper, or other substance, through which liquors are passed for defecation; a strainer.

[imp. & p. p. FILTERED; p. pr. & vb. n. FILTERING.] [Fr. filtrer, Sp. filtrar, It. feltrare, filtrare. See supra.] To purify or defecate, as liquor, by causing it to pass through a filter, or a porous substance that retains feculent matter.

n. Same as PHILTER, q. v.