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definitions

filtering operation

[fĭl′tə-rĭng]
n.
  1. The surgical creation of a fistula between the anterior chamber of the eye and the subconjunctival space, as for glaucoma.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.