HEEL, (I) that part of the foot in man which is situated below and behind the ankle by analogy, the calcaneal part of the tarsus in other vertebrates. The heel proper in digitigrades and ungulates is raised off the ground and is commonly known as the "knee" or "hock," while the term "heel" is applied to the hind hoofs; (2) to turn over to one side, especially of a ship.