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procerus muscle

[prō-sîr′əs]
n.
  1. A muscle with origin from the membrane covering the bridge of the nose, with insertion into the frontal bone, with nerve supply from a branch of the facial nerve, and whose action assists the frontal bone.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.