valve Noun A device that controls the flow of a gas or fluid through a pipe.
valve Noun A device that admits fuel and air into the cylinder of an internal combustion engine, or one that allows combustion gases to exit.
valve Noun One or more membranous partitions, flaps, or folds, which permit the passage of the contents of a vessel or cavity in one direction, but stop or retard the flow in the opposite direction; as, the ileocolic, mitral, and semilunar valves.
valve Noun A vacuum tube.
valve Noun One of the pieces into which certain fruits naturally separate when they dehisce.
valve Noun A small portion of certain anthers, which opens like a trapdoor to allow the pollen to escape, as in the barberry.
valve Noun One of the pieces or divisions of bivalve or multivalve shells.
valve Noun One of the two similar portions of the shell of a diatom.