'talus' originates from Latin, specifically the word 'talus', where it meant 'ankle' or the ankle bone.

'talus' was borrowed into English from Latin (via Neo-Latin/scientific Latin). The anatomical sense dates from early scientific usage; the geological and fortification senses developed later by analogy to a sloping or projecting part.

Initially, it meant 'ankle' or 'ankle bone'; over time the term was extended metaphorically to mean 'a sloping mass or slope at a base' (as in rock debris at a cliff base or the sloped base of a wall).