fly bridge vs flybridge

fly bridge and flybridge both are nouns.

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

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

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

Other synonyms of fly bridge include flying bridge, monkey bridge.

fly bridge (noun)	flybridge (noun)
the highest navigational bridge on a ship; a small (often open) deck above the pilot house	the highest navigational bridge on a ship; a small (often open) deck above the pilot house