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pars tympanica

[tĭm-păn′ĭ-kə]
n.
  1. The tympanic portion of the temporal bone, forming the greater part of the wall of the external acoustic meatus.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.