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instrument

n. · v.
US //ˈɪnstɹəmənt// UK //ˈɪnstɹəmənt// in·stru·ment
  1. 1 musical device (n.)
    A2 Elementary Music

    an object used for playing or making music.

    a device specifically designed or adapted to produce musical sounds.

    Example

    She practiced playing her instrument for two hours every afternoon.

    Example

    The orchestra consists of several different families of instruments, including strings, woodwinds, brass, and percussion.
    • musical instrument
  2. 2 measuring tool (n.)
    B1 Intermediate Science

    a tool used for doing very exact work or measuring something.

    a tool or implement used for precise physical work, scientific observation, or measurement.

    Example

    The surgeon reached for a sharp instrument to begin the operation.

    Example

    The laboratory was equipped with delicate instruments designed to detect even the slightest changes in atmospheric pressure.
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  1. 3 aviation/navigation (n.)
    B2 Upper Intermediate Technical Science

    a dial or screen in a plane or car that shows information like speed.

    a measuring device that provides data for the control and operation of a vehicle or machine.

    Example

    The pilot checked the instruments to make sure the plane was at the right height.

    Example

    During the storm, the pilot had to rely entirely on his flight instruments because visibility was near zero.
  2. 4 legal document (n.)
    C1 Advanced Formal Technical Law

    a formal legal paper, such as a contract or a will.

    a formal legal document that creates, confirms, or records a right or liability.

    Example

    The lawyer prepared the legal instrument for the sale of the house.

    Example

    A negotiable instrument, such as a cheque or a promissory note, must be signed by the maker to be valid.
  3. 5 a means of doing something (n.)
    B2 Upper Intermediate

    something or someone used to make a specific result happen.

    a person or thing that is used as a means to achieve a particular aim.

    Example

    The new law was an instrument for social change in the country.

    Example

    The diplomat acted as an instrument of peace, facilitating communication between the two warring factions.
  4. 6 to add sensors (v.)
    C2 Proficiency Technical Science

    to add measuring tools or sensors to a machine or system.

    to equip a vehicle, machine, or system with measuring devices or sensors for monitoring performance.

    Example

    Engineers had to instrument the bridge to monitor how it moved in the wind.

    Example

    The prototype was heavily instrumented to collect data on thermal stress during high-speed testing.
Origin

From Middle English instrument, from Old French instrument, from Latin īnstrūmentum (“an implement, tool”), From īnstruō (“build, construct; arrange”) + -mentum.

Word family

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