Rhamnus californicus vs California buckthorn

Rhamnus californicus and California buckthorn both are nouns.

Word	Noun	Adjective	Verb	Adverb
Rhamnus californicus	Yes	No	No	No
California buckthorn	Yes	No	No	No

As nouns, Rhamnus californicus and California buckthorn are synonyms defined as:

Rhamnus californicus and California buckthorn: evergreen shrub of western United States bearing small red or black fruits

Other synonyms of Rhamnus californicus include California coffee, coffeeberry.

Rhamnus californicus (noun)	California buckthorn (noun)
evergreen shrub of western United States bearing small red or black fruits	evergreen shrub of western United States bearing small red or black fruits