The term 'jawbone' refers to the bones of the lower face, which are composed of the JOWL (4 letters), MAXILLA (7 letters), and MANDIBLE (8 letters). The JOWL is located at the back of the jaw and is the largest bone in the lower face. The MAXILLA is located at the upper part of the jaw and is responsible for the movement of the upper jaw. The MANDIBLE is located at the lower part of the jaw and is responsible for the movement of the lower jaw. Together, these three bones form the jawbone, which is essential for chewing and speaking.