noun. any of several trees of the genus Cinchona.
noun. medicinal bark of cinchona trees; source of quinine and quinidine.
1. Noun, singular or mass Quinine is made from the bark of the cinchona tree and gives tonic water its signature bitter taste. 2. Adjective Bitterness comes from esoteric ingredients you can order online, like gentian or cinchona bark, or you can clean and roast a few dandelion roots (yes, dandelion!)