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definitions

supinator muscle

[sōō′pə-nā′tər]
n.
  1. A muscle with origin from the humerus and the ulna, with insertion into the radius, with nerve supply from the radial nerve, and whose action supinates the forearm.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.