valve

American  

[valv] / vælv /

noun

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. Anatomy. 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. (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.

   1. one of the two or more separable pieces composing certain shells.

   2. either half of the silicified shell of a diatom.

6. Botany.

   1. one of the segments into which a capsule dehisces.

   2. a flap or lidlike part of certain anthers.

7. Electronics (chiefly British). vacuum tube.

8. Archaic. one of the leaves of a double or folding door.

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verb (used with object)

valved, valving

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

valve British  

/ vælv /

noun

1. any device that shuts off, starts, regulates, or controls the flow of a fluid

2. anatomy 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 diode triode tetrode pentode

4. zoology any of the separable pieces that make up the shell of a mollusc

5. music 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. botany

   1. any of the several parts that make up a dry dehiscent fruit, esp a capsule

   2. either of the two halves of a diatom cell wall

7. archaic a leaf of a double door or of a folding door

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valve Scientific  

/ vălv /

1. 1. Any of various mechanical devices that control the flow of liquids, gases, or loose material through pipes or channels by blocking and uncovering openings.

   2. The movable part or element of such a device.

2. Any of various structures that prevent the backward flow of a body fluid, such as blood or lymph. Valves in the heart, veins, and lymphatic vessels contain flaps (known as cusps) that close in response to pressure created by the backflow of fluid.

3. One of the paired hinged shells of certain mollusks, such as clams and oysters.

4. See electron tube

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Other Word Forms

• undervalve noun
• valveless adjective
• valvelike adjective

Etymology

Origin of valve

1350–1400; Middle English < Latin valvae leaves of a door

Example Sentences

Workers at the Evonik plant were dispatched to close the gas supply valve into the factory, where the German chemical maker produces silica for toothpaste and food products.

From The Wall Street Journal

On Feb. 18, 2015, there was an explosion at the refinery, then operated by ExxonMobil, caused by the rupture of an eroded valve.

From Los Angeles Times

Silver, which led the liquidation, will likely continue to lead volatility — either by stabilizing later or by remaining the pressure valve for risk.

From MarketWatch

They happen when water treatment works become overwhelmed, usually after rainfall, allowing highly diluted sewage to spill into a river as a "safety valve".

From BBC

The piston faces have small, crescent-shaped reliefs into which the valves extend near the top dead center.

From The Wall Street Journal

Related Words

• faucet
• pipe
• spigot