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per·cus·sion (pər-kŭshən)
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n.
1. The striking together of two bodies, especially when noise is produced.
2. The sound, vibration, or shock caused by the striking together of two bodies.
3. The act of detonating a percussion cap in a firearm.
4. A method of medical diagnosis in which various areas of the body, especially the chest, back, and abdomen, are tapped to determine by resonance the condition of internal organs.
5. Music
a. The section of a band or orchestra composed of percussion instruments.
b. Percussion instruments or their players considered as a group.

[Latin percussiō, percussiōn-, from percussus, past participle of percutere, to percuss; see PERCUSS.]

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2019 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 

Indo-European & Semitic Roots Appendices

    Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

    Indo-European Roots

    Semitic Roots

    The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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