or cola nut Caffeine-containing nut of two evergreen trees (Cola acuminata and C. nitida) of the cocoa family (Sterculiaceae), native to tropical Africa and cultivated extensively in the New World tropics. The trees grow to 60 ft (18.3 m) in height and have oblong leathery leaves, yellow flowers, and star-shaped fruit. The nut has been used in medicines and in soft drinks, though American "colas" today instead use synthetic flavorings that mimic its taste. Kola nuts are also used where grown as a medium of exchange or are chewed to diminish sensations of hunger and fatigue, to aid digestion, and to combat intoxication, hangover, and diarrhea