n.
Pronunciation: ˌ se-f ə -l ə - ' z ā -sh ə n
Function: noun
Date: 1864
: a tendency in the evolution of organisms to concentrate the sensory and neural organs in an anterior head
n.
Pronunciation: ˌ se-f ə -l ə - ' z ā -sh ə n
Function: noun
Date: 1864
: a tendency in the evolution of organisms to concentrate the sensory and neural organs in an anterior head
Merriam Webster Collegiate English Dictionary. Merriam Webster - Энциклопедический словарь английского языка. 2012