stinking horehound vs black archangel

stinking horehound and black archangel both are nouns.

Word	Noun	Adjective	Verb	Adverb
stinking horehound	Yes	No	No	No
black archangel	Yes	No	No	No

As nouns, stinking horehound and black archangel are synonyms defined as:

stinking horehound and black archangel: ill-smelling European herb with rugose leaves and whorls of dark purple flowers

Other synonyms of stinking horehound include Ballota nigra, black horehound, fetid horehound.

stinking horehound (noun)	black archangel (noun)
ill-smelling European herb with rugose leaves and whorls of dark purple flowers	ill-smelling European herb with rugose leaves and whorls of dark purple flowers