sunberry vs black nightshade

sunberry and black nightshade both are nouns.

Word	Noun	Adjective	Verb	Adverb
sunberry	Yes	No	No	No
black nightshade	Yes	No	No	No

As nouns, black nightshade is a hypernym of sunberry; that is, black nightshade is a word with a broader meaning than sunberry:

sunberry: improved garden variety of black nightshade having small edible orange or black berries
black nightshade: Eurasian herb naturalized in America having white flowers and poisonous hairy foliage and bearing black berries that are sometimes poisonous but sometimes edible

Other hypernyms of sunberry include common nightshade, poison-berry, poisonberry, Solanum nigrum.

sunberry (noun)	black nightshade (noun)
improved garden variety of black nightshade having small edible orange or black berries	Eurasian herb naturalized in America having white flowers and poisonous hairy foliage and bearing black berries that are sometimes poisonous but sometimes edible