See Also: Pulmonic Valve (also called pulmonary valve)(health)
valve(dictionary)
D valve(medicine)
Valve(health)
VALVE(medicine)
valve(encyclopedia)
valve(2)(dictionary)
valve(1)(dictionary)
nasal valve(medicine)
nonrebreathing valve(medicine)

valve(1) (iou)



valve noun. [valv] LME.
[Latin valva leaf of a door (usu. pl. valvae a folding door).]
I.
a. Each of the leaves of a folding door; either of the halves of a double door. arch. LME.
b. A door regulating the flow of water in a lock or sluice. Now rare. L18.
Zoology. Either of the halves of the hinged shell of a bivalve mollusc, brachiopod, etc.; any of the parts of the compound shell of a barnacle etc. M17.
Botany.
a. Each of the halves or sections into which a dry fruit (esp. a pod or capsule) or an anther dehisces. M18.
b. Either of the overlapping halves of the cell wall of a diatom. M19.
Entomology. Any of various (usu. paired) plates or lobes, esp. associated with the genitals; a valvula. E19.
II.
Anatomy & Zoology etc.
a. A membranous fold in a hollow organ or tubular structure of the circulatory system, digestive tract, etc., which automatically closes to prevent the reflux of blood or other contents. E17.
b. A similar part or structure serving to close or protect an aperture, as in the ear, throat, etc. E19.
Mechanics. A device in a pipe or aperture that controls the passage of air, steam, water, etc.; esp. one acting automatically by yielding to pressure in one direction only. M17.
Music. A device for extending the range of pitch of a brass instrument by increasing or decreasing the effective length of the tube. L19.
Electronics. = THERMIONIC valve. E20.
A move in a chess problem which opens one line while simultaneously shutting off another. M20.
Comb.: valve gear the mechanism that controls the opening and closing of the cylinder valves in a steam engine or internal-combustion engine; valve head Mechanics the part of a lift valve that is lifted off the valve aperture to open the valve; valve train Mechanics in an internal-combustion engine, the gearing and linkages by which the crankshaft is caused to open and close a valve at the proper time.
valveless adjective M19.
valvelet noun (rare) a small valve, a valvule L18.
valviform adjective (Zoology) valve-shaped E19.