Skull: Part of the axial skeleton, which is made up of 80 bones. The bones that form the head. The skull is made up of cranial bones (bones that surround and protect the brain) and facial bones (bones that form the eye sockets, nose, cheeks, jaw, and other parts of the face). An opening at the base of the skull is where the spinal cord connects to the brain. The skull is composed of 29 bones, 8 forming the cranium, 14 forming the bones of the face, 6 forming the small bones in the middle ear, and 1 hyoid bone.