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definitions

acystia

[ā-sĭs′tē-ə, ə-sĭs′-]
n.
  1. Congenital absence of the urinary bladder.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.