COFFEE-BERRY (Rhamnus californicus), a North Amer ican shrub of the buckthorn family (Rhamnaceae), called also pigeon-berry and yerba del oso, native to canyons and mountain slopes in California. It grows usually about 5 ft. high, bears oblong, finely toothed, pointed leaves; small, greenish flowers, and a round berry, black when ripe, containing usually two somewhat coffee like nutlets. (See BUCKTHORN ; CASCARA SAGRADA. )