Norway rat vs Rattus norvegicus

Norway rat and Rattus norvegicus both are nouns.

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

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

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

Other synonyms of Norway rat include brown rat.

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