1.NounEither of the two main arteries that supply blood to the head of which the left in humans arises from the arch of the aorta and the right by bifurcation of the brachiocephalic artery with each passing up the side of the neck and dividing opposite the upper border of the thyroid cartilage into an external branch supplying the face, tongue, and external parts of the head and an internal branch supplying the brain, eye, and other internal parts of the head.
2.AdjectiveOf or pertaining to the carotid artery.