flight of steps vs stairway

flight of steps and stairway both are nouns.

Word	Noun	Adjective	Verb	Adverb
flight of steps	Yes	No	No	No
stairway	Yes	No	No	No

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

flight of steps: a stairway (set of steps) between one floor or landing and the next
stairway: a way of access (upward and downward) consisting of a set of steps

Other hypernyms of flight of steps include staircase.

flight of steps (noun)	stairway (noun)
a stairway (set of steps) between one floor or landing and the next	a way of access (upward and downward) consisting of a set of steps