Meaning

noun a temporary passageway of planks (as over mud on a building site)

noun a temporary bridge for getting on and off a vessel at dockside

noun passageway between seating areas as in an auditorium or passenger vehicle or between areas of shelves of goods as in stores

originFrom Middle English gangway, from Old English gangweġ (“passageway; thoroughfare”), equivalent to gang + way. Related to Dutch gang (“hallway”) and Norwegian gang (“hallway”).

Etymology from Wiktionary, CC BY-SA 3.0