flyover vs flying

flyover and flying both are nouns.

Word	Noun	Adjective	Verb	Adverb
flyover	Yes	No	No	No
flying	Yes	Yes	No	No

As nouns, flying is a hypernym of flyover; that is, flying is a word with a broader meaning than flyover:

flyover: a flight at a low altitude (usually of military aircraft) over spectators on the ground
flying: an instance of traveling by air

Other hypernyms of flyover include flight.

flyover (noun)	flying (noun)
a flight at a low altitude (usually of military aircraft) over spectators on the ground	an instance of traveling by air
bridge formed by the upper level of a crossing of two highways at different levels

flyover (adjective)	flying (adjective)
	hurried and brief
	moving swiftly