Either of the two perforated substances of the brain, designated anterior and posterior.perforated space
Everyday English Words With Ancient Arabic RootsThroughout the English language are Arabic roots. Read on for the surprising Arabian delights in English. English would be awfully bland without them.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.