razorbill vs Alca torda

razorbill and Alca torda both are nouns.

Word	Noun	Adjective	Verb	Adverb
razorbill	Yes	No	No	No
Alca torda	Yes	No	No	No

As nouns, razorbill and Alca torda are synonyms defined as:

razorbill and Alca torda: black-and-white northern Atlantic auk having a compressed sharp-edged bill

Other synonyms of razorbill include razor-billed auk.

razorbill (noun)	Alca torda (noun)
black-and-white northern Atlantic auk having a compressed sharp-edged bill	black-and-white northern Atlantic auk having a compressed sharp-edged bill