（1）meningitis 脑膜炎 mening + itis

Inflammation(炎症) of the meninges(脑膜) of the brain and the spinal cord(脊髓), most often caused by a bacterial or viral infection and characterized by fever, vomiting, intense headache, and stiff neck.

[Date: 1800-1900; Language: Latin; Origin: meninx 'outer part of the brain' + English -itis]

meninges

n. Plural of meninx.

meninx

n. A membrane, especially one of the three membranes enclosing the brain and spinal cord in vertebrates(脊椎动物).

[Greek mēninx.]

-itis

suff. Inflammation or disease of:

i.e. tonsillitis (=infection of the tonsils[扁桃体]) 

（2）encephalitis 脑炎 encephal + itis

Inflammation of the brain.

[Date: 1800-1900; Language: Greek; Origin: enkephalos 'brain' + English -itis]

encephal-

pref. Variant of encephalo-.

encephalo-

pref. Brain: encephalitis. 

[New Latin, from Greek (muelos) enkephalos, '(marrow) in the head': en-, 'in' + kephalē, 'head']

marrow

髓；骨髓；精华；活力