cortical vs cortex

cortical is not a noun while cortex is a noun.

Word	Noun	Adjective	Verb	Adverb
cortical	No	Yes	No	No
cortex	Yes	No	No	No

cortical (noun)	cortex (noun)
	the tissue forming the outer layer of an organ or structure in plant or animal
	the layer of unmyelinated neurons (the grey matter) forming the cortex of the cerebrum
	the tissue that surrounds the lens nucleus

cortical (adjective)	cortex (adjective)
of or relating to a cortex