Definition of filter

• n. - 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.
• n. - To purify or defecate, as water or other liquid, by causing it to pass through a filter.
• v. i. - To pass through a filter; to percolate.
• n. - Same as Philter.