buffalo bur vs nightshade

buffalo bur and nightshade both are nouns.

Word	Noun	Adjective	Verb	Adverb
buffalo bur	Yes	No	No	No
nightshade	Yes	No	No	No

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

buffalo bur: North American nightshade with prickly foliage and racemose yellow flowers
nightshade: any of numerous shrubs or herbs or vines of the genus Solanum; most are poisonous though many bear edible fruit

buffalo bur (noun)	nightshade (noun)
North American nightshade with prickly foliage and racemose yellow flowers	any of numerous shrubs or herbs or vines of the genus Solanum; most are poisonous though many bear edible fruit