mountain blacksnake vs blacksnake

mountain blacksnake and blacksnake both are nouns.

Word	Noun	Adjective	Verb	Adverb
mountain blacksnake	Yes	No	No	No
blacksnake	Yes	No	No	No

As nouns, mountain blacksnake and blacksnake are synonyms defined as:

mountain blacksnake and blacksnake: large harmless shiny black North American snake

Other synonyms of mountain blacksnake include black rat snake, Elaphe obsoleta, pilot blacksnake.

mountain blacksnake (noun)	blacksnake (noun)
large harmless shiny black North American snake	blackish racer of the eastern United States that grows to six feet
	large harmless shiny black North American snake