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Landström's muscle

[länd′strœmz′]
n.
  1. Microscopic muscle fibers that are attached to the eyelids and to the anterior orbital fascia, and that draw the eyeball forward and the lids backward.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.