flight vs Underground Railroad

flight and Underground Railroad both are nouns.

Word	Noun	Adjective	Verb	Adverb
flight	Yes	No	Yes	No
Underground Railroad	Yes	No	No	No

flight (noun)	Underground Railroad (noun)
an instance of traveling by air	secret aid to escaping slaves that was provided by abolitionists in the years before the American Civil War
the act of escaping physically
a scheduled trip by plane between designated airports
a stairway (set of steps) between one floor or landing and the next
passing above and beyond ordinary bounds
an air force unit smaller than a squadron
a formation of aircraft in flight
a flock of flying birds
the path followed by an object moving through space