big shellbark vs big shellbark hickory

big shellbark and big shellbark hickory both are nouns.

Word	Noun	Adjective	Verb	Adverb
big shellbark	Yes	No	No	No
big shellbark hickory	Yes	No	No	No

As nouns, big shellbark and big shellbark hickory are synonyms defined as:

big shellbark and big shellbark hickory: hickory of the eastern United States resembling the shagbark but having a much larger nut

Other synonyms of big shellbark include big shagbark, Carya laciniosa, king nut, king nut hickory.

big shellbark (noun)	big shellbark hickory (noun)
hickory of the eastern United States resembling the shagbark but having a much larger nut	hickory of the eastern United States resembling the shagbark but having a much larger nut