fly bridge vs monkey bridge

fly bridge and monkey bridge both are nouns.

Word	Noun	Adjective	Verb	Adverb
fly bridge	Yes	No	No	No
monkey bridge	Yes	No	No	No

As nouns, fly bridge and monkey bridge are synonyms defined as:

fly bridge and monkey bridge: the highest navigational bridge on a ship; a small (often open) deck above the pilot house

Other synonyms of fly bridge include flybridge, flying bridge.

fly bridge (noun)	monkey bridge (noun)
the highest navigational bridge on a ship; a small (often open) deck above the pilot house	a high narrow platform above a deck or in an engine room or boiler room
	the highest navigational bridge on a ship; a small (often open) deck above the pilot house