Aorta: The great artery, or trunk of the arterial system.
It proceeds from the left ventricle of the heart, giving origin to all the arteries, except the pulmonary arteries. It first rises, when it is called the ascending aorta; then makes a great curve, when it gives off branches to the head, and upper extremities; then proceeds downwards, gives off branches to the trunk, and supplies the pelvis and lower extremities.
The ancient Greek word ἀορτή, which means aorta, comes from the verb ἀείρω (to lift, to rise up).