filter

tip n. 1 filter on a cigarette removing some impurities. 2 cigarette with this.  filter-tipped adj.

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.