tympanomastoid fissure

[tĭm′pə-nō-măstoid′]
n.
  1. A fissure that separates the tympanic portion from the mastoid portion of the temporal bone and transmits the auricular branch of the vagus nerve.auricular fissure
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.