tropicbird vs boatswain bird

tropicbird and boatswain bird both are nouns.

Word	Noun	Adjective	Verb	Adverb
tropicbird	Yes	No	No	No
boatswain bird	Yes	No	No	No

As nouns, tropicbird and boatswain bird are synonyms defined as:

tropicbird and boatswain bird: mostly white web-footed tropical seabird often found far from land

Other synonyms of tropicbird include tropic bird.

tropicbird (noun)	boatswain bird (noun)
mostly white web-footed tropical seabird often found far from land	mostly white web-footed tropical seabird often found far from land