| Term | Definition |
| compact bone | dense, hard bone tissue found primarily in the shafts of long bones and on the outer surfaces of other bones |
| spongy bone | softer bone with a spongy appearance |
| haversian system | microscopic, structural unit of compact bone also called the osteon |
| axial skeleton | the central part of the skeleton that contains the skull, spine, ribs and sternum |
| appendicular skeleton | the part of the skeleton that contains the pelvis and extremities |
| trabeculae | plate arrangement of spongy bone |
| diaphysis | long shaft of bone |
| epiphysis | the enlarged ends of long bones |
| epiphysial disc | band of cartilage at the end of long bones, also called the growth plate |
| medullary cavity | hollow center of the diaphysis |
| endosteum | lining of the medullary cavity |
| periosteum | outside covering of the diaphysis |
| articular cartilage | forms the outer surface of the epiphysis |
| ossification | the formation of bone |
| osteoblasts | bone forming cells |
| osteoclasts | bone-destroying cells |
| bone resorption | process whereby osteoclasts breakdown bone matrix |
| trochanter | a large tubercle found only on the femur |
| foramen | an opening in a bone |
| fossa | a depression or groove in a bone |
| meatus | tunnel or tubelike passageway |
| fracture | broken bone |
| cranium | bony structure that encases and protects the brain |
| frontal bone | bone that forms the forehead |
| parietal bones | bones that form the upper sides of the head |
| temporal bones | bone on the side of the head near the ears |
| external auditory meatus | opening for the ear |
| zygomatic process | part of the temporal bone that forms part of the cheekbone |
| styloid process | sharp projection from the bottom of the temporal bone |
| mastoid process | part of the temporal bone that attaches to some of the muscles of the neck |
| occipital bone | the bone found at the back and base of the skull |
| foramen magnum | large hole in the occipital bone where the brainstem extends down |
| occipital condyles | parts of the occipital bone that sit on the vertebral column |
| spenoid bone | butterfly shaped bone that forms part of the floor and sides of the cranium |
| sella turcica | a depression in the sphenoid bone that is home to the pituitary gland |
| ethmoid bone | irregularly shaped bone located between the eye orbits |
| mandible | lower jaw bone |
| temporomandibular joint | where the mandible articulates with the temporal bone |
| maxilla | upper jaw |
| palatine bones | form the posterior part of the hard palate and the floor of the nasal cavity |
| zygomatic bones | cheekbones |
| sinuses | air-filled cavities |
| sutures | skull joints |
| fontanels | soft spots in infant skulls |
| hyoid bone | U-shaped bone in the upper neck that anchors the tongue |
| ossicles | bones of the middle ear |
| vertebral column | backbone |
| cervical vertabrae | neck bones |
| vertebra prominens | found at C7 |
| thoracic vertebrae | backbones in the chest area |
| lumbar vertebrae | bones of lower back |
| sacrum | forms the posterior wall of the pelvis |
| coccyx | tailbone |
| atlas | C1, it supports the skull, allows you to nod yes |
| axis | C2, allows your head to rotate from side to side, say no |
| vertebral foramen | opening for the spinal cord |
| intervertebral disc | supports and cushions vertebrae |
| spina bifida | failure of the lamina to fuse during fetal development |
| scoliosis | lateral curvature of the spine |
| kyphosis | exaggerated thoracic curvature |
| lordosis | exaggerated lumbar curvature |
| sternum | manubrium, body, and xiphoid process |
| true ribs | top 7 pairs of ribs that attach directly to the sternum by costal cartilage |
| false ribs | ribs that attach indirectly to the sternum or not at all |
| floating ribs | bottom 2 pairs of ribs that lack sternal attachment |
| intercostal muscles | muscles in between ribs |
| costal margin | edges of the cartilage that form an angle as they converge near the xyphoid process |
| angle of Louis | used in counting ribs, it is at the level of the second rib |