nonevent vs event

nonevent and event both are nouns.

Word	Noun	Adjective	Verb	Adverb
nonevent	Yes	No	No	No
event	Yes	No	No	No

As nouns, event is a hypernym of nonevent; that is, event is a word with a broader meaning than nonevent:

nonevent: an anticipated event that turns out to be far less significant than was expected
event: something that happens at a given place and time

nonevent (noun)	event (noun)
an anticipated event that turns out to be far less significant than was expected	something that happens at a given place and time
	a phenomenon located at a single point in space-time; the fundamental observational entity in relativity theory
	a phenomenon that follows and is caused by some previous phenomenon
	a special set of circumstances