Northern lobster vs Homarus americanus

Northern lobster and Homarus americanus both are nouns.

Word	Noun	Adjective	Verb	Adverb
Northern lobster	Yes	No	No	No
Homarus americanus	Yes	No	No	No

As nouns, Northern lobster and Homarus americanus are synonyms defined as:

Northern lobster and Homarus americanus: lobster of Atlantic coast of America

Other synonyms of Northern lobster include American lobster, Maine lobster.

Northern lobster (noun)	Homarus americanus (noun)
lobster of Atlantic coast of America	lobster of Atlantic coast of America
flesh of cold-water lobsters having large tender claws; caught from Maine to the Carolinas