uneven vs unevenness

uneven is not a noun while unevenness is a noun.

Word	Noun	Adjective	Verb	Adverb
uneven	No	Yes	No	No
unevenness	Yes	No	No	No

uneven (noun)	unevenness (noun)
	the quality of being uneven and lacking uniformity
	the quality of being unbalanced

uneven (adjective)	unevenness (adjective)
not even or uniform as e.g. in shape or texture
not divisible by two
lacking consistency
(of a contest or contestants) not fairly matched as opponents
variable and recurring at irregular intervals