Real Dictionary

ginseng
uncountable noun: Ginseng is the root of a plant found in countries such as China, Russia, and America which some people believe is good for your health.

ginseng in American English
any of several perennial herbs (genus Panax) of the ginseng family, with thick, forked, aromatic roots, esp. a Chinese species (P. pseudoginseng) and a North American species (P. quinquefolium)
designating a family (Araliaceae, order Apiales) of dicotyledonous plants, shrubs, and trees, usually having flat clusters of small, white or greenish flowers and, often, fragrant leaves, including Hercules'- club and English ivy
noun: any of several plants of the genus Panax, esp. P. pseudoginseng, of eastern Asia, or P. qinquefolius, of North America, having an aromatic root used medicinally

ginseng in British English
noun: either of two araliaceous plants, Panax schinseng of China or P. quinquefolius of North America, whose forked aromatic roots are used medicinally