Meaning of vasospasm

vas•o•spasm

Pronunciation: (vas'ō-spaz"um, vā'zō-), [key]
— n.
  1. sudden constriction of an artery, leading to a decrease in its diameter and in the amount of blood it can deliver.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.