Stories We Like: A Guide to the Comma
1540s, "pertaining to the two great arteries of the neck," from Greek karotides "great arteries of the neck," plural of karotis, from karoun "plunge into sleep or stupor," because compression of these arteries was believed to cause unconsciousness (Galen). But if this is folk etymology, the Greek word could be from kara "head," related to kranion "skull, upper part of the head," from PIE root *ker- "horn, head" (see horn (n.)).
carotid ca·rot·id (kə-rŏt'ĭd)
Either of two major arteries, one on each side of the neck, that carry blood to the head. adj.
Relating to either of these arteries.
carotid artery n.
An artery that originates on the right from the brachiocephalic artery and on the left from the aortic arch, runs upward into the neck and divides opposite the upper border of the thyroid cartilage, with the external and internal carotid arteries as its terminal branches; common carotid artery.
An artery with its origin in the common carotid artery, with branches to the superior thyroid, lingual, facial, occipital, posterior auricular, and ascending pharyngeal arteries, and with the maxillary and superficial temporal arteries as its terminal branches; external carotid artery.
An artery that arises from the common carotid artery opposite the upper border of the thyroid cartilage and terminates in the middle cranial fossa by dividing into the anterior and the middle cerebral arteries; internal carotid artery.
one of several arteries that supply blood to the head and neck. Of the two common carotid arteries, which extend headward on each side of the neck, the left originates in the arch of the aorta over the heart; the right originates in the brachiocephalic trunk, the largest branch from the arch of the aorta. Each common carotid artery divides into an external and an internal carotid artery.