messiness vs mess

messiness and mess both are nouns.

Word	Noun	Adjective	Verb	Adverb
messiness	Yes	No	No	No
mess	Yes	No	Yes	No

As nouns, messiness and mess are synonyms defined as:

Other synonyms of messiness include muss, mussiness.

messiness (noun)	mess (noun)
the trait of being untidy and messy	a (large) military dining room where service personnel eat or relax
a state of confusion and disorderliness	a meal eaten in a mess hall by service personnel
	soft semiliquid food
	(often followed by `of') a large number or amount or extent
	a state of confusion and disorderliness
	informal terms for a difficult situation

messiness (verb)	mess (verb)
	make a mess of or create disorder in
	eat in a mess hall