What does "instrument" mean?

Instrument: A contrivance or implement, by which musical sounds are produced; as, a musical instrument. Praise him with stringed instruments and organs. Ps. cl.

Additional senses

  1. 2.But signs when songs and instruments he hears. Dryden.
  2. 3.(Law) A writing, as the means of giving formal expression to some act; a writing expressive of some act, contract, process, as a deed, contract, writ, etc. Burrill.
  3. 4.One who, or that which, is made a means, or is caused to serve a purpose; a medium, means, or agent. Or useful serving man and instrument, To any sovereign state. Shak. The bold are but the instruments of the wise. Dryden.
  4. 5.To perform upon an instrument; to prepare for an instrument; as, a sonata instrumented for orchestra.

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