ETYM Old Eng. bon, ban, AS. bân; akin to Icel. bein, Swed. ben, Dan. and Dutch been, German bein bone, leg; cf. Icel. beinn straight.
1. A shade of white the color of bleached bones; SYN. ivory, pearl, off-white.
2. Rigid connective tissue that makes up the skeleton of vertebrates; SYN. os.
3. The porous calcified substance from which bones are made; SYN. osseous tissue.
Hard connective tissue comprising the skeleton of most vertebrate animals. Bone is composed of a network of collagen fibers impregnated with mineral salts (largely calcium phosphate and calcium carbonate), a combination that gives it great density and strength, comparable in some cases with that of reinforced concrete. Enclosed within this solid matrix are bone cells, blood vessels, and nerves. The interior of the long bones of the limbs consists of a spongy matrix filled with a soft marrow that produces blood cells.
There are two types of bone: those that develop by replacingcartilage and those that form directly from connective tissue. The latter, which includes the bones of the cranium, are usually platelike in shape and form in the skin of the developing embryo. Humans have about 206 distinct bones in the skeleton, of which the smallest are the three ossicles in the middle ear.
A bone of a fish.