Wordnet 3.0
NOUN (1)
1. 
 that part of the central nervous system that includes all the higher nervous centers; 
 enclosed within the skull; 
 continuous with the spinal cord; 
[syn: brain, encephalon]
The Collaborative International Dictionary of English v.0.48:
encephalon \en*ceph"a*lon\, n.; pl. encephala. [NL. See
   Encephalos.] (Anat.)
   The contents of the cranium; the brain.
   [1913 Webster]
WordNet (r) 3.0 (2006):
encephalon
    n 1: that part of the central nervous system that includes all
         the higher nervous centers; enclosed within the skull;
         continuous with the spinal cord [syn: brain,
         encephalon]