Sentence:  German chemists were the first to isolate pure drug chemicals from herbal medicines, with the isolation of morphine from crude opium in 1803 and quinine from the bark of the <WSD>cinchona</WSD> tree in 1820. 
Meaning of the word marked with <WSD> tags:  A tree or shrub of the genus "Cinchona", native to the Andes in South America but since widely cultivated in Indonesia and India as well for its medicinal bark.