Barnaby's thistle vs yellow star-thistle

Barnaby's thistle and yellow star-thistle both are nouns.

Word	Noun	Adjective	Verb	Adverb
Barnaby's thistle	Yes	No	No	No
yellow star-thistle	Yes	No	No	No

As nouns, Barnaby's thistle and yellow star-thistle are synonyms defined as:

Barnaby's thistle and yellow star-thistle: European weed having a winged stem and hairy leaves; adventive in the eastern United States

Other synonyms of Barnaby's thistle include Centaurea solstitialis.

Barnaby's thistle (noun)	yellow star-thistle (noun)
European weed having a winged stem and hairy leaves; adventive in the eastern United States	European weed having a winged stem and hairy leaves; adventive in the eastern United States