invariability vs uneven

invariability is a noun but uneven is not a noun.

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

invariability (noun)	uneven (noun)
the quality of being resistant to variation
a quality of uniformity and lack of variation

invariability (adjective)	uneven (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