ENGLISH
REFERENCE

valve

n. · v.
US //ˈvæɫv// UK //vˈælv// valve
  1. 1 mechanical device (n.)
    B2 Upper Intermediate Technical

    a mechanical part in a pipe or machine that opens and closes to control the flow of water, gas, or air.

    a mechanical device used to regulate the flow of fluids or gases within a system of pipes or machinery.

    Example

    He turned the valve to shut off the water before fixing the leak.

    Example

    The engineer adjusted the pressure relief valve to ensure the steam did not exceed the safety limits of the boiler system.

    Usage

    Often used with verbs like 'open', 'close', or 'turn'.
  2. 2 anatomy (n.)
    B2 Upper Intermediate Medicine

    a part of the heart or a vein that keeps blood flowing in the right direction.

    a membranous fold or flap in a hollow organ or vessel that maintains the unidirectional flow of bodily fluids.

    Example

    The doctor checked the patient's heart valves to make sure they were working correctly.

    Example

    Mitral valve prolapse occurs when the flaps of the heart's mitral valve do not close smoothly or evenly.

    Usage

    Commonly appears in medical contexts regarding the heart or circulatory system.
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  1. 3 vacuum tube (n.)
    C1 Advanced British English Technical Computing

    an old-fashioned electronic part used in early radios and computers.

    an electron tube consisting of a sealed glass or metal enclosure used to control electron flow.

    Example

    The old radio still uses glass valves instead of modern chips.

    Example

    Early mainframe computers relied on thousands of thermionic valves, which generated immense heat and required frequent replacement.

    Teacher's tip

    This is the standard British term for what Americans call a 'vacuum tube'.
  2. 4 biology (n.)
    C2 Proficiency Technical Science

    one of the two parts of a shell, like those on a clam or an oyster.

    one of the distinct, usually hinged, shells of a bivalve mollusc or the shell-like parts of certain other organisms.

    Example

    The clam uses strong muscles to keep its two valves tightly shut.

    Example

    The fossil record provides clear evidence of how the hinge mechanism between the two valves evolved over millions of years.
  3. 5 to regulate flow (v.)
    C2 Proficiency Formal Technical

    to control the flow of something using a valve.

    to regulate or control the passage of a fluid or gas through the use of valves.

    Example

    The system is designed to valve the gas automatically if the pressure drops.

    Example

    The technician had to manually valve the intake to prevent the chemical solution from overflowing the primary tank.
Origin

From Middle English valve, from Latin valva (“double door, valve”). Doublet of valva.

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