cranium

n. skull

The skull is a bony structure found in many animals which serves as the general framework for the head. The skull supports the structures of the face and protects the head against injury. The skull can be subdivided into two parts: the cranium and the mandible. A skull that is missing a mandible is only a cranium; this is the source of a very commonly made error in terminology. Those animals having skulls are called craniates. Protection of the brain is only one part of the function of a bony skull. For example, a fixed distance between the eyes is essential for stereoscopic vision, and a fixed position for the ears helps the brain to 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.
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Cranium /cra·ni·um/ pl. cra´nia [L.] the skeleton of the head, variously construed as including all of the bones of the head except the mandible, [more]Cranium - Community and Resources

Noun
1. the part of the skull that encloses the brain
(synonym) braincase, brainpan
(hypernym) bone, os
(part-holonym) skull
(part-meronym) asterion

(n.)
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.