A bruit is the sound of blood flowing through a narrowed portion of an artery. The sound means that the blood flow may be partially blocked; artery blockage is most often due to atherosclerosis (hardening of the arteries).
A doctor can hear the sound by listening with a stethoscope placed over an artery, such as the carotid artery in the neck. Bruits in the carotid arteries may be a sign that a blood vessel is partially blocked, which may increase the person's risk for having a transient ischemic attack (TIA) or stroke.
WebMD Medical Reference from Healthwise