rose pink vs American centaury

rose pink and American centaury both are nouns.

Word	Noun	Adjective	Verb	Adverb
rose pink	Yes	No	No	No
American centaury	Yes	No	No	No

As nouns, rose pink and American centaury are synonyms defined as:

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

Other synonyms of rose pink include bitter floom, marsh pink, Sabbatia Angularis, Sabbatia stellaris.

rose pink (noun)	American centaury (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