(1) paste usually with a polyester base which, when mixed with a hardener, forms a surface which can be sanded smooth and is suitable for repairs to dented or rusted bodywork. Also called "filler paste."

(2) A primer filler.

(3) an inert material added to paper, resins, and other substances to modify their poroperties and improve quality.

(4) An opening through which some liquid can be poured (i.e., oil or gasoline).