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megacystic syndrome

[mĕg′ə-sĭs′tĭk]
n.
  1. A syndrome characterized by a large thin-walled bladder, regurgitation of the urine into the ureters, and dilated ureters.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.