ragwort vs butterweed

ragwort and butterweed both are nouns.

Word	Noun	Adjective	Verb	Adverb
ragwort	Yes	No	No	No
butterweed	Yes	No	No	No

As nouns, ragwort and butterweed are synonyms defined as:

Other synonyms of ragwort include Senecio glabellus.

ragwort (noun)	butterweed (noun)
widespread European weed having yellow daisylike flowers; sometimes an obnoxious weed and toxic to cattle if consumed in quantity	any of several yellow-flowered plants of the genus Packera; often placed in genus Senecio
American ragwort with yellow flowers	American ragwort with yellow flowers