VALVES

A device that controls the flow of a gas or fluid through a pipe.

A device that admits fuel and air into the cylinder of an internal combustion engine, or one that allows combustion gases to exit.

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 control the flow in the opposite direction

"the ileocolic, mitral, and semilunar valves"

To control (flow) by means of a valve.