gangway vs footbridge

gangway and footbridge both are nouns.

Word	Noun	Adjective	Verb	Adverb
gangway	Yes	No	No	No
footbridge	Yes	No	No	No

As nouns, footbridge is a hypernym of gangway; that is, footbridge is a word with a broader meaning than gangway:

Other hypernyms of gangway include overcrossing, pedestrian bridge.

gangway (noun)	footbridge (noun)
a temporary passageway of planks (as over mud on a building site)	a bridge designed for pedestrians
a temporary bridge for getting on and off a vessel at dockside
passageway between seating areas as in an auditorium or passenger vehicle or between areas of shelves of goods as in stores