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sphenoparietal sinus

[sfē′nō-pə-rī′ĭ-təl]
n.
  1. A paired sinus of the dura mater that begins on the parietal bone and empties into the cavernous sinus.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.