smallpox virus vs variola virus

smallpox virus and variola virus both are nouns.

Word	Noun	Adjective	Verb	Adverb
smallpox virus	Yes	No	No	No
variola virus	Yes	No	No	No

As nouns, smallpox virus and variola virus are synonyms defined as:

smallpox virus and variola virus: the virus that causes smallpox in humans; can be used as a bioweapon

smallpox virus (noun)	variola virus (noun)
the virus that causes smallpox in humans; can be used as a bioweapon	the virus that causes smallpox in humans; can be used as a bioweapon