a tendency in the development of animals to localization of important organs or parts in or near the head.
Origin of cephalization
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
(in the evolution of animals) development of a head by the concentration of feeding and sensory organs and nervous tissue at the anterior end
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
1864, coined by U.S. zoologist James D. Dana (1813-1895) from Greek kephale "head" (see cephalo-) on model of specialization, etc.
Online Etymology Dictionary, © 2010 Douglas Harper