healing herb vs comfrey

healing herb and comfrey both are nouns.

Word	Noun	Adjective	Verb	Adverb
healing herb	Yes	No	No	No
comfrey	Yes	No	No	No

As nouns, healing herb and comfrey are synonyms defined as:

healing herb and comfrey: leaves make a popular tisane; young leaves used in salads or cooked

healing herb (noun)	comfrey (noun)
leaves make a popular tisane; young leaves used in salads or cooked	leaves make a popular tisane; young leaves used in salads or cooked
	perennial herbs of Europe and Iran; make rapidly growing groundcover for shaded areas