[ trahy-seps ]
/ ˈtraɪ sɛps /
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noun, plural tri·ceps·es [trahy-sep-siz], /ˈtraɪ sɛp sɪz/, tri·ceps.Anatomy.
a muscle having three heads or points of origin, especially the muscle on the back of the arm, the action of which straightens the elbow.


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Origin of triceps

1570–80; <Latin: three-headed, equivalent to tri-tri- + -ceps, stem -cipit- -headed, derivative of caput head
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022

How to use triceps in a sentence

British Dictionary definitions for triceps

/ (ˈtraɪsɛps) /

noun plural -cepses (-sɛpsɪz) or -ceps
any muscle having three heads, esp the one (triceps brachii) that extends the forearm

Word Origin for triceps

C16: from Latin, from tri- + caput head
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medical definitions for triceps

[ trīsĕps′ ]

n. pl. tri•ceps•es (-sĕp′sĭz)
A three-headed muscle of the upper arm, whose long or scapular head has origin from the lateral border of the scapula, the lateral head, origin from the lateral and posterior surface of the humerus, and the medial head from the posterior surface of the humerus; with insertion into the olecranon of the ulna, with nerve supply from the radial nerve, and whose action extends the forearm; the triceps brachii.
The gastrocnemius and soleus muscles of the calf considered as one muscle; the triceps surae.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Scientific definitions for triceps

[ trīsĕps′ ]

The muscle at the back of the upper arm that raises and lowers the forearm. The triceps has three points of attachment to bone at its origin.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.