Quinine n. : An alkaloid extracted from the bark of several species of cinchona (esp. Cinchona Calisaya) as a bitter white crystalline substance, C20H24N2O2. Hence, by extension (Med.), any of the salts of this alkaloid, as the acetate, chloride, sulphate, etc., employed as a febrifuge or antiperiodic. Called also quinia, quinina, etc.

Example:
How to prune a 40 feet cinchona (Quinine) tree?

Taxonomy
quinine, malaria, quinine sulfate, quinine dihydrochloride, bark, quinine tonic, quinine total synthesis, treatment, dose, ingredient, cinchona, cinchona bark, drugs, hydrochloride, used to treat, uncomplicated malaria, treatment of malaria, Brit.

Defination from the web:
Quinine (US: /ˈkwaɪnaɪn/, UK: /kwɪˈniːn, ˈkwɪniːn/) is a natural white crystalline alkaloid having antipyretic (fever-reducing), antimalarial, ... Quinine is available with a prescription in the United States and over-the-counter, in very small quantities, in tonic water. ...