cola or kola, tropical tree (genus Cola) of the family Sterculiaceae (sterculia family), native to Africa but now grown in other tropical regions. The fruit is a pod containing seeds from which is obtained caffeine, an alkaloid that functions as a stimulant. Cola nuts are chewed by the local populations and are exported for commercial use in soft drinks and medicines. Colas are classified in the division Magnoliophyta, class Magnoliopsida, order Malvales, family Sterculiaceae.

Rienzi or Rienzo, Cola di, 1313?-1354, Roman popular leader. In 1343 on a mission to Pope Clement VI at Avignon, he won the papal confidence. While there he befriended Petrarch. Returning to Rome as papal votary, he won great popular support and received (May, 1347) wide dictatorial powers, which he claimed to hold under the pope's sovereignty. He crushed the barons and began great reforms in an effort to rouse an Italian national conscience. Calling himself tribune of the sacred Roman republic, he sought to rally the support of the other Italian cities and dreamed of a popular Italian empire with Rome as the capital. The pope, aroused by his policies, incited the barons against him. Renzi was defeated (Dec., 1347) and fled. At Prague in 1350 he disclosed to Holy Roman Emperor Charles IV his conviction that they shared a call to regenerate the Roman Catholic Church and the world. Charles, however, responded by jailing him and in 1352 sent him to Avignon to face the Inquisition. The new pope, Innocent VI, subsequently absolved and freed Rienzi and sent him with Cardinal Albornoz to Italy. The cardinal made him senator, and Rienzi entered Rome in triumph, but his violent and arbitrary rule soon resulted in a popular uprising and in his murder. In modern times Rienzi has been idealized as a forerunner of Italian nationalism.

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.

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