Compact bone, also called cortical bone, is the hard, stiff, smooth, thin, white bone tissue that surrounds all bones in the human body. It is also called osseous tissue or cortical bone and it provides structure and support for an organism as part of its skeleton, in addition to being a location for the storage of minerals like calcium.

Compact bone, also known as cortical bone, is a denser material used to create much of the hard structure of the skeleton. As seen in the image below, compact bone forms the cortex, or hard outer shell of most bones in the body. The remainder of the bone is formed by cancellous or spongy bone.

Compact bone, also called cortical bone, dense bone in which the bony matrix is solidly filled with organic ground substance and inorganic salts, leaving only tiny spaces (lacunae) that contain the osteocytes, or bone cells.