robusta coffee vs Coffea robusta

robusta coffee and Coffea robusta both are nouns.

Word	Noun	Adjective	Verb	Adverb
robusta coffee	Yes	No	No	No
Coffea robusta	Yes	No	No	No

As nouns, robusta coffee and Coffea robusta are synonyms defined as:

robusta coffee and Coffea robusta: native to West Africa but grown in Java and elsewhere; resistant to coffee rust

Other synonyms of robusta coffee include Coffea canephora, Rio Nunez coffee.

robusta coffee (noun)	Coffea robusta (noun)
native to West Africa but grown in Java and elsewhere; resistant to coffee rust	native to West Africa but grown in Java and elsewhere; resistant to coffee rust