Definition of Circle of WillisCircle of Willis: A critical arterial circle at the base of the brain. The circle of Willis receives all the blood that is pumped up the two internal carotid arteries that come up the front of the neck. All the principal arteries that supply the two halves of the brain (hemispheres) branch off from the circle of Willis. Last Editorial Review: 3/19/2012
Back to MedTerms online medical dictionary A-Z List Need help identifying pills and medications? |
Get the latest health and medical information delivered direct to your inbox FREE!


