valve

UK: /ˈvælv/ US: /vælv/ ,(valv)

Inflections of 'valve' (v): (⇒ conjugate)

valves

v 3rd person singular

valving

v pres p

valved

v past

valved

v past p

WordReference Random House Learner's Dictionary of American English © 2025

valve /vælv/   n., v., valved, valv•ing. 
n. [countable]

1. any device for halting or controlling the flow of something, as a liquid, through a pipe or other passage.
2. a hinged lid or other movable part that closes or changes the passage in such a device.
3. a structure in the body that permits the flow of a fluid, as blood, in one direction only:
   a heart valve.
4. Music and Dance (in musical wind instruments of the trumpet class) a device for changing the length of the air column so as to alter the pitch of a tone.
5. Zoology one of the two or more separable pieces that make up certain shells:
   the valves of a clamshell.

v. [~ + object]

6. to provide with a valve.

WordReference Random House Unabridged Dictionary of American English © 2025

valve (valv),  n., v., valved, valv•ing. 

n. 

1. any device for halting or controlling the flow of a liquid, gas, or other material through a passage, pipe, inlet, outlet, etc.
2. a hinged lid or other movable part that closes or modifies the passage in such a device.
3. [Anat.] a membranous fold or other structure that controls the flow of a fluid, as one that permits blood to flow in one direction only.
4. Music and Dance (in musical wind instruments of the trumpet class) a device for changing the length of the air column to alter the pitch of a tone.
5. Zoology
   • one of the two or more separable pieces composing certain shells.
   • either half of the silicified shell of a diatom.
6. [Bot.]
   • Botany one of the segments into which a capsule dehisces.
   • Botany a flap or lidlike part of certain anthers.
7. Electronics See vacuum tube (def. 1).
8. [Archaic.] one of the leaves of a double or folding door.

v.t. 

9. to provide with a means of controlling the flow of liquid, gas, etc., by inserting a valve.

• Latin valvae leaves of a door
• Middle English 1350–1400

valve′less, adj. 
valve′like′, adj. 

Collins Concise English Dictionary © HarperCollins Publishers::

valve / vælv/ noun

1. any device that shuts off, starts, regulates, or controls the flow of a fluid
2. a flaplike structure in a hollow organ, such as the heart, that controls the one-way passage of fluid through that organ
3. Also called: tube, vacuum tube an evacuated electron tube containing a cathode, anode, and, usually, one or more additional control electrodes. When a positive potential is applied to the anode, electrons emitted from the cathode are attracted to the anode, constituting a flow of current which can be controlled by a voltage applied to the grid to produce amplification, oscillation, etc
   See also diode2, triode1, tetrode, pentode
4. any of the separable pieces that make up the shell of a mollusc
5. a device on some brass instruments by which the effective length of the tube may be varied to enable a chromatic scale to be produced
6. any of the several parts that make up a dry dehiscent fruit, esp a capsule
7. a leaf of a double door or of a folding door

Etymology: 14th Century: from Latin valva a folding door

ˈvalveless adjective

ˈvalveˌlike adjective