fountain grass vs Pennisetum setaceum

fountain grass and Pennisetum setaceum both are nouns.

Word	Noun	Adjective	Verb	Adverb
fountain grass	Yes	No	No	No
Pennisetum setaceum	Yes	No	No	No

As nouns, fountain grass and Pennisetum setaceum are synonyms defined as:

fountain grass and Pennisetum setaceum: tall perennial ornamental grass with long nodding flower plumes of tropical Africa and Asia

Other synonyms of fountain grass include Pennisetum ruppelii.

fountain grass (noun)	Pennisetum setaceum (noun)
tall perennial ornamental grass with long nodding flower plumes of tropical Africa and Asia	tall perennial ornamental grass with long nodding flower plumes of tropical Africa and Asia