bluebill vs scaup

bluebill and scaup both are nouns.

Word	Noun	Adjective	Verb	Adverb
bluebill	Yes	No	No	No
scaup	Yes	No	No	No

As nouns, bluebill and scaup are synonyms defined as:

bluebill and scaup: diving ducks of North America having a bluish-grey bill

Other synonyms of bluebill include broadbill, scaup duck.

bluebill (noun)	scaup (noun)
diving ducks of North America having a bluish-grey bill	diving ducks of North America having a bluish-grey bill