Rattus norvegicus vs Norway rat

Rattus norvegicus and Norway rat both are nouns.

Word	Noun	Adjective	Verb	Adverb
Rattus norvegicus	Yes	No	No	No
Norway rat	Yes	No	No	No

As nouns, Rattus norvegicus and Norway rat are synonyms defined as:

Rattus norvegicus and Norway rat: common domestic rat; serious pest worldwide

Other synonyms of Rattus norvegicus include brown rat.

Rattus norvegicus (noun)	Norway rat (noun)
common domestic rat; serious pest worldwide	common domestic rat; serious pest worldwide