cal·ca·ne·us / kalˈkānēəs/ (also cal·ca·ne·um / -nēəm/ ) • n. (pl. -ne·i / -nēˌī; -nēˌē/ or -ne·a / -nēə/ ) Anat. the large bone forming the heel. It articulates with the cuboid bone of the foot and the talus bone of the ankle, and the Achilles tendon (or tendo calcaneus) is attached to it.

calcaneus (heel bone) (kal-kay-niŭs) n. the large bone in the tarsus of the foot that forms the projection of the heel behind the foot.