columbo vs American gentian

columbo and American gentian both are nouns.

Word	Noun	Adjective	Verb	Adverb
columbo	Yes	No	No	No
American gentian	Yes	No	No	No

As nouns, columbo and American gentian are synonyms defined as:

columbo and American gentian: any of various tall perennial herbs constituting the genus Frasera; widely distributed in warm dry upland areas of California, Oregon, and Washington

Other synonyms of columbo include American columbo, deer's-ear, deer's-ears, pyramid plant.

columbo (noun)	American gentian (noun)
any of various tall perennial herbs constituting the genus Frasera; widely distributed in warm dry upland areas of California, Oregon, and Washington	any of various tall perennial herbs constituting the genus Frasera; widely distributed in warm dry upland areas of California, Oregon, and Washington