(anatomy) A sphincter muscle valve that separates the small intestine and the large intestine. Its critical function is to limit the reflux of colonic contents into the ileum.

(anatomy) ileocecal valve

plural of overhead valve

(engineering) A valve; especially one hinged at one edge, which, when raised from its seat, falls with a clacking sound.

plural of ball valve

plural of Bauhin's valve

plural of thermionic valve

(anatomy) Any of the valves in the heart which prevent blood from moving in the wrong direction.

(automotive) A type of internal combustion engine design which has the inlet and exhaust valves in the cylinder head (and therefore above the piston). The camshaft can be beside the pistons (with pushrods and rockers operating the valves) or above the valves, with the latter usually referred to as overhead cam.

(automotive) A type of internal combustion engine design which has the inlet and exhaust valves in the cylinder block beside the piston. The cylinder head is then a simple dome extending across the valves and piston.