Achilles Tendon
a tendon, so called because, as fable reports, Thetis, the mother of Achilles, held him by that part when she dipped him in the river Styx to make him invulnerable. It is the strong and powerful tendon of the heel, which is formed by the junction of divers muscles, and which extends from the calf to the heel. When this tendon is cut or ruptured, the use of the leg is immediately lost; and, unless the parts be afterward successfully united, the patient will remain a cripple for life.