[gwahr-uh-nah, gwahr-uh-nah] 
| 1. | a woody, climbing shrub Paullinia cupana, of the soapberry family, growing in parts of South America, having seeds that contain caffeine and are used in soft drinks. |
| 2. | a drink containing extract of guarana seed. |
guarana
(Paullinia cupana), woody, climbing plant, of the soapberry family (Sapindaceae), native to the Amazon Basin. It has a smooth, erect stem; large leaves with five oblong-oval leaflets; clusters of short-stalked flowers; and fruit about the size of a grape and usually containing one seed shaped like a tiny horse chestnut.
Learn more about guarana with a free trial on Britannica.com.