What is the X in X-mas?
encephalitis en·ceph·a·li·tis (ěn-sěf'ə-lī'tĭs)
n. pl. en·ceph·a·lit·i·des (-lĭt'ĭ-dēz)
Inflammation of the brain. Also called cephalitis.
An inflammation of the brain. Encephalitis may be caused by a virus or lead poisoning, or it may be a complication of another disease, such as influenza or measles. Encephalitis can cause permanent brain damage or death. It is also possible, however, to recover from it completely.