talus

from The Century Dictionary.

• noun In anat: The ankle or ankle-joint: as, os tali, the bone of the ankle.
• noun The ankle-bone or huckle-bone; the astragalus.
• noun In ornithology, same as calcaneum, 2.
• noun That variety of clubfoot in which the heel rests on the ground and the toes are drawn up; talipes calcaneus.
• noun In entomology, the apex or distal end of the tibia, articulated with the tarsus.
• noun In architecture, the slope or inclination of any work, as of a wall inclined on its face, either by decreasing its thickness toward the summit or by leaning it against a bank.
• noun In fort, the slope of a work, as a bastion, rampart, or parapet.
• noun The mass of rocky fragments which lies at the base of a cliff or precipitous rock, and which has been formed by the accumulation of pieces brought down from above by the action of gravity, rain, frost, etc.; scree; debris; wash. See these words.

from the GNU version of the Collaborative International Dictionary of English.

• noun (Anat.) The astragalus.
• noun (Surg.) A variety of clubfoot (Talipes calcaneus). See the Note under Talipes.
• noun (Fort.) A slope; the inclination of the face of a work.
• noun (Geol.) A sloping heap of fragments of rock lying at the foot of a precipice.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun anatomy The bone of the ankle.
• noun geology A sloping heap of fragments of rock lying at the foot of a precipice.
• noun architecture The slope of an embankment wall, which is thicker at the bottom than at the top.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a sloping mass of loose rocks at the base of a cliff
• noun the bone in the ankle that articulates with the leg bones to form the ankle joint