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definitions

quadrate pronator muscle

n.
  1. A muscle with origin from the anterior surface of the ulna, with insertion into the anterior surface of the radius, with nerve supply from the anterior interosseous nerve, and whose action pronates the forearm.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.