noun in·stru·ment \ˈin(t)-strə-mənt\

Definition of instrument

  1. 1 :  a device used to produce music; also :  a singing voice

  2. 2a :  a means whereby something is achieved, performed, or furtheredb :  one used by another as a means or aid :  dupe, tool

  3. 3 :  implement; especially :  one designed for precision work

  4. 4 :  a formal legal document (as a deed, bond, or agreement)

  5. 5a :  a measuring device for determining the present value of a quantity under observationb :  an electrical or mechanical device used in navigating an airplane; especially :  such a device used as the sole means of navigating

Examples of instrument in a sentence

  1. an instrument designed to measure the Earth's atmosphere

  2. The piano was his favorite musical instrument.

  3. Do you play any instruments?

Origin and Etymology of instrument

Middle English, from Anglo-French, from Latin instrumentum, from instruere to arrange, instruct

First Known Use: 14th century

Synonym Discussion of instrument

implement, tool, instrument, appliance, utensil mean a relatively simple device for performing work. implement may apply to anything necessary to perform a task crude stone implements farm implements. tool suggests an implement adapted to facilitate a definite kind or stage of work and suggests the need of skill more strongly than implement a carpenter's tools. instrument suggests a device capable of delicate or precise work the dentist's instruments. appliance refers to a tool or instrument utilizing a power source and suggests portability or temporary attachment household appliances. utensil applies to a device used in domestic work or some routine unskilled activity kitchen utensils.



verb in·stru·ment \ˈin(t)-strə-ˌment\

Definition of instrument

  1. transitive verb
  2. 1 :  to address a legal instrument to

  3. 2 :  to score for musical performance :  orchestrate

  4. 3 :  to equip with instruments especially for measuring and recording data


First Known Use of instrument


INSTRUMENT Defined for English Language Learners



noun in·stru·ment \ˈin(t)-strə-mənt\

Definition of instrument for English Language Learners

  • : a tool or device used for a particular purpose; especially : a tool or device designed to do careful and exact work

  • : a device that measures something (such as temperature or distance)

  • : a device that is used to make music

INSTRUMENT Defined for Kids


noun in·stru·ment \ˈin-strə-mənt\

Definition of instrument for Students

  1. 1 :  a tool or device for doing a particular kind of work a dentist's instruments

  2. 2 :  a device used to produce music

  3. 3 :  a way of getting something done Curiosity is an instrument of discovery.

  4. 4 :  a legal document (as a deed)

  5. 5 :  a device that measures something (as altitude or temperature)

Medical Dictionary


noun in·stru·ment \ˈin(t)-strə-mənt\

Medical Definition of instrument

  1. :  any implement, tool, or utensil (as for surgery)

Law Dictionary


noun in·stru·ment

Legal Definition of instrument

  1. 1 :  a means or implement by which something is achieved, performed, or furthered an instrument of crime

  2. 2 :  a document (as a deed, will, bond, note, certificate of deposit, insurance policy, warrant, or writ) evidencing rights or duties especially of one party to another under the law a person is not liable on an instrument unless the person signed the instrumentUniform Commercial Code an indictment is a form of charging instrument; specifically :  negotiable instrument

Seen and Heard

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to criticize severely

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