henbane vs black henbane

henbane and black henbane both are nouns.

Word	Noun	Adjective	Verb	Adverb
henbane	Yes	No	No	No
black henbane	Yes	No	No	No

As nouns, henbane and black henbane are synonyms defined as:

henbane and black henbane: poisonous fetid Old World herb having sticky hairy leaves and yellow-brown flowers; yields hyoscyamine and scopolamine

Other synonyms of henbane include Hyoscyamus niger, stinking nightshade.

henbane (noun)	black henbane (noun)
poisonous fetid Old World herb having sticky hairy leaves and yellow-brown flowers; yields hyoscyamine and scopolamine	poisonous fetid Old World herb having sticky hairy leaves and yellow-brown flowers; yields hyoscyamine and scopolamine