sweet elder vs American elder

sweet elder and American elder both are nouns.

Word	Noun	Adjective	Verb	Adverb
sweet elder	Yes	No	No	No
American elder	Yes	No	No	No

As nouns, sweet elder and American elder are synonyms defined as:

sweet elder and American elder: common elder of central and eastern North America bearing purple-black berries; fruit used in wines and jellies

Other synonyms of sweet elder include black elderberry, Sambucus canadensis.

sweet elder (noun)	American elder (noun)
common elder of central and eastern North America bearing purple-black berries; fruit used in wines and jellies	common elder of central and eastern North America bearing purple-black berries; fruit used in wines and jellies