Dictionary Meaning and Definition on 'Cranium'
n : the part of the skull that encloses the brain [syn: braincase,
[also: crania (pl)]
- Cranium \Cra"ni*um\ (kr?"n?-?m), n.; pl. E. Craniums (-?mz),
L. Crania (-?). [NL., fr. Gr. ????; akin to ??? head.]
The skull of an animal; especially, that part of the skull,
either cartilaginous or bony, which immediately incloses the
brain; the brain case or brainpan. See Skull.
Wikipedia Meaning and Definition on 'Cranium'
The skull is a bony structure in the head of many animals that supports the structures of the face and protects the brain from injury.
The skull is composed of two parts: the cranium and the mandible. A skull without a mandible is only a cranium. Animals that have skulls are called craniates.
Functions of the skull include protection of the brain, fixing the distance between the eyes to allow stereoscopic vision, and fixing the position of the ears to help the brain use auditory cues to judge direction and distance of sounds. In some animals, the skull also has a defensive function (e.g. horned ungulates); the frontal bone is where horns are mounted.
In humans, the adult skull is normally made up of 22 bones. Except for the mandible, all of the bones of the skull are joined together by sutures, rigid articulations permitting very little movement. Eight bones —including one frontal, two parietals, one occipital bone, one sphenoid, two temporals and one ethmoid— form the neurocranium (braincase), a protective vault surrounding the brain. Fourteen bones form the splanchnocranium, the bones supporting the face. Encased within the temporal bones are the six ear ossicles of the middle ears, though these are not part of the skull. The hyoid bone, supporting the tongue, is usually not considered as part of the skull either, as it does not articulate with any other bones. The skull is a protector of the brain.[See more about Cranium at Dictionary 3.0 Encyclopedia]