Situated or occurring beneath the arachnoid membrane, or between the arachnoid and the pia mater: subarachnoid space; subarachnoid anesthesia. (adjective)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "subarachnoid" in a sentence
"Sharon Stone, as you know, Larry, had a very difficult situation in September of 2001, where she had a splitting headache and something called a subarachnoid hemorrhage, and she almost died."
"Brain aneurysms are often discovered when they rupture, causing bleeding into the brain or the space closely surrounding the brain called the subarachnoid space, causing a subarachnoid hemorrhage."
"Michaels, 47, suffered a type of stroke called a subarachnoid haemorrhage, which causes bleeding in the fluid-filled spaces around the base of the brain."