coca vs coca plant

coca and coca plant both are nouns.

Word	Noun	Adjective	Verb	Adverb
coca	Yes	No	No	No
coca plant	Yes	No	No	No

As nouns, coca and coca plant are synonyms defined as:

coca and coca plant: a South American shrub whose leaves are chewed by natives of the Andes; a source of cocaine

Other synonyms of coca include Erythroxylon coca.

coca (noun)	coca plant (noun)
dried leaves of the coca plant (and related plants that also contain cocaine); chewed by Andean people for their stimulating effect	a South American shrub whose leaves are chewed by natives of the Andes; a source of cocaine
a South American shrub whose leaves are chewed by natives of the Andes; a source of cocaine