The heelbone or calcaneus is a robust bone located in the foot, responsible for providing support and absorbing shock while walking, running, or jumping. There are several synonyms for the word heelbone, including os calcis, calcaneal bone, and heel bone. The os calcis is the Latin term for this bone, which means "heel bone." The calcaneal bone describes the bone's location and function, coming from the Latin word "calx," which means "heel." The term "heel bone" is also self-explanatory, representing the bone's position and shape. Regardless of the term used, it is essential to keep the heelbone healthy and protected to ensure optimal performance and mobility.