valve

noun

ˈvalv 

1

a

: any of numerous mechanical devices by which the flow of liquid, gas, or loose material in bulk may be started, stopped, or regulated by a movable part that opens, shuts, or partially obstructs one or more ports or passageways

also : the movable part of such a device

b

: a device in a brass instrument for quickly channeling air flow through an added length of tube in order to change the fundamental tone by some definite interval

c

chiefly British : electron tube

2

[borrowed from Medieval Latin valva, going back to Latin] : a bodily structure (such as the mitral valve) that closes temporarily a passage or orifice or permits movement of fluid in one direction only

3

[borrowed from New Latin valva, going back to Latin] : one of the distinct usually hinged and movable pieces of which the shell of some shell-bearing animals (such as lamellibranch mollusks, brachiopods, and barnacles) consists

4

[borrowed from New Latin valva, going back to Latin]

a

: one of the segments or pieces into which a dehiscing capsule or legume separates

b

: the portion of various anthers (as of the barberry) resembling a lid

c

: one of the two encasing membranes of a diatom

5

archaic : a leaf of a folding or double door

valved

ˈvalvd 

adjective

valveless

ˈvalv-ləs 

adjective

Synonyms

• cock
• faucet
• gate
• spigot
• stopcock
• tap

Examples of valve in a Sentence

They turned off the main water valve to the house.

Recent Examples on the Web

Protect your hose lines from damage by opening the end valves and draining them thoroughly before winter hits. —Lauren Landers, Better Homes & Gardens, 17 Oct. 2024

However, her immense restraint isn’t afforded a release valve at any point, causing her character to plateau. —Siddhant Adlakha, Variety, 5 Oct. 2024

Styrene is a toxic and flammable chemical and crews had to cool the tank with water until the valve closed. —Quinlan Bentley, The Enquirer, 1 Oct. 2024

The towering flame had greatly subsided by this morning, four days after a vehicle drove through a fence and struck an above-ground valve, causing a massive pipeline explosion and fire that burned for days in the Deer Park/La Porte area. —Allyson Ackerman, Chron, 19 Sep. 2024

Word History

Etymology

Middle English, "leaf of a folding door," borrowed from Latin valva (usually in plural valvae) "double or folding door, leaf of such a door," perhaps going back to an early derivative of the base of volvere "to roll, make turn" — more at wallow entry 1

First Known Use

14th century, in the meaning defined at sense 5

Phrases Containing valve

• ball valve
• bicuspid valve
• brake/valve job
• butterfly valve
• check valve
• escape valve
• mitral valve
• safety valve
• semilunar valve
• slide valve
• tricuspid valve

Kids Definition

valve

noun

ˈvalv 

1

: a bodily structure (as in a vein or the heart) that closes temporarily to prevent passage of material or that allows movement of a fluid in one direction only

2

a

: a mechanical device by which the flow of liquid, gas, or loose material in bulk may be controlled by a movable part

also : the movable part of such a device

b

: a device in a brass musical instrument for quickly changing the tube length in order to make the tone higher or lower

3

: one of the separate pieces that make up the shell of some animals (as clams) and are often hinged

4

: one of the pieces into which a ripe seed capsule or pod separates

valved

ˈvalvd 

adjective

Medical Definition

valve

noun

ˈvalv 

1

: a bodily structure (as the mitral valve) that closes temporarily a passage or orifice or permits movement of fluid in one direction only

2

: any of various mechanical devices by which the flow of liquid (as blood) may be started, stopped, or regulated by a movable part that opens, shuts, or partially obstructs one or more ports or passageways

also : the movable part of such a device