acoustic meatus

n.
  1. The passage leading inward through the tympanic portion of the temporal bone, from the auricle to the tympanic membrane; external acoustic meatus.
  2. A canal running through the petrous portion of the temporal bone, giving passage to the facial and vestibulocochlear nerves and to the labyrinthine artery and veins; internal acoustic meatus.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.