American centaury vs bitter floom

American centaury and bitter floom both are nouns.

Word	Noun	Adjective	Verb	Adverb
American centaury	Yes	No	No	No
bitter floom	Yes	No	No	No

As nouns, American centaury and bitter floom are synonyms defined as:

American centaury and bitter floom: any of several pink-flowered marsh plant of the eastern United States resembling a true centaury

Other synonyms of American centaury include marsh pink, rose pink, Sabbatia Angularis, Sabbatia stellaris.

American centaury (noun)	bitter floom (noun)
any of several pink-flowered marsh plant of the eastern United States resembling a true centaury	any of several pink-flowered marsh plant of the eastern United States resembling a true centaury