check ligament of eyeball

[chĕk]
n.
  1. Either of two expansions of the sheaths of the medial and lateral rectus muscles of the eyeball that act to restrain the activity of these muscles.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.