Erigeron pulchellus vs robin's plantain

Erigeron pulchellus and robin's plantain both are nouns.

Word	Noun	Adjective	Verb	Adverb
Erigeron pulchellus	Yes	No	No	No
robin's plantain	Yes	No	No	No

As nouns, Erigeron pulchellus and robin's plantain are synonyms defined as:

Erigeron pulchellus and robin's plantain: common perennial of eastern North America having flowers with usually violet-purple rays

Erigeron pulchellus (noun)	robin's plantain (noun)
common perennial of eastern North America having flowers with usually violet-purple rays	common perennial of eastern North America having flowers with usually violet-purple rays