Ballota nigra vs fetid horehound

Ballota nigra and fetid horehound both are nouns.

Word	Noun	Adjective	Verb	Adverb
Ballota nigra	Yes	No	No	No
fetid horehound	Yes	No	No	No

As nouns, Ballota nigra and fetid horehound are synonyms defined as:

Ballota nigra and fetid horehound: ill-smelling European herb with rugose leaves and whorls of dark purple flowers

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

Ballota nigra (noun)	fetid horehound (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