Quinine (noun)

1. A bitter crystalline alkaloid, used as an antimalarial drug and also in tonic water.
2. A medicine or other substance used to treat or prevent malaria.

Origin:

Early 19th century: from french quinine, from spanish quinina, named after the peruvian indigenous word for cinchona bark.

Examples:

1. Quinine was once the only effective treatment for malaria.
2. The bitter taste of quinine is often masked by adding sugar or fruit juice to the tonic water.
3. Quinine is produced from the bark of the cinchona tree and has a long history of use in traditional medicine.
4. Quinine is still used in some parts of the world to treat malaria and other infectious diseases.
5. The discovery of quinine was a major milestone in the fight against malaria and other tropical diseases.