oriental cockroach vs oriental roach

oriental cockroach and oriental roach both are nouns.

Word	Noun	Adjective	Verb	Adverb
oriental cockroach	Yes	No	No	No
oriental roach	Yes	No	No	No

As nouns, oriental cockroach and oriental roach are synonyms defined as:

oriental cockroach and oriental roach: dark brown cockroach originally from orient now nearly cosmopolitan in distribution

Other synonyms of oriental cockroach include Asiatic cockroach, blackbeetle, Blatta orientalis.

oriental cockroach (noun)	oriental roach (noun)
dark brown cockroach originally from orient now nearly cosmopolitan in distribution	dark brown cockroach originally from orient now nearly cosmopolitan in distribution