liftoff vs ascent

liftoff and ascent both are nouns.

Word	Noun	Adjective	Verb	Adverb
liftoff	Yes	No	No	No
ascent	Yes	No	No	No

As nouns, ascent is a hypernym of liftoff; that is, ascent is a word with a broader meaning than liftoff:

Other hypernyms of liftoff include ascension, rise, rising.

liftoff (noun)	ascent (noun)
the initial ascent of a rocket from its launching pad	the act of changing location in an upward direction
	a movement upward; rise above the ground
	an upward slope or grade (as in a road)