ungregarious vs gregariousness

ungregarious is not a noun while gregariousness is a noun.

Word	Noun	Adjective	Verb	Adverb
ungregarious	No	Yes	No	No
gregariousness	Yes	No	No	No

ungregarious (noun)	gregariousness (noun)
	the quality of being gregarious--having a dislike of being alone

ungregarious (adjective)	gregariousness (adjective)
(of animals) not gregarious
(of plants) growing together in groups that are not close together
not disposed to seek company