triceps

tri·ceps   (trī'sěps')    (click for larger image in new window) n.   pl. tri·ceps·es (-sěp'sĭz) also triceps A large three-headed muscle running along the back of the upper arm and serving to extend the forearm. [From Latin, three-headed : tri-, tri- + caput, head; see kaput- in Indo-European roots.]

triceps 

Main Entry: tri·ceps
Pronunciation: 'trI-"seps
Function: noun
Inflected Form: plural triceps also tri·ceps·es
: a muscle that arises from three heads: a : the large extensor muscle that is situated along the back of the upper arm, arises by the long head from the infraglenoid tubercleof the scapula and by two heads from the shaft of the humerus, is inserted into the olecranon at the elbow, and extends the forearm at the elbow joint called also triceps brachii b : the gastrocnemius and soleus muscles viewed as constituting together one muscle called also triceps surae

triceps tri·ceps (trī'sěps')
n. pl. tri·ceps·es (-sěp'sĭz) or triceps

1. 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.

2. The gastrocnemius and soleus muscles of the calf considered as one muscle; the triceps surae.

triceps   (trī'sěps')  Pronunciation Key  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.