n.
Any of several syndromes in which blood vessels or nerves are compressed, usually by an overlying muscle, as they pass from the neck region to the arm, causing pain, numbness, and weakness of the arm and hand.
The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.