terrain flight vs flying

terrain flight and flying both are nouns.

Word	Noun	Adjective	Verb	Adverb
terrain flight	Yes	No	No	No
flying	Yes	Yes	No	No

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

Other hypernyms of terrain flight include flight.

terrain flight (noun)	flying (noun)
flight at very low altitudes	an instance of traveling by air

terrain flight (adjective)	flying (adjective)
	hurried and brief
	moving swiftly