n 1  :  a bitter crystalline alkaloid C₂₀H₂₄N₂O₂ from cinchona bark used in medicine  2  :  a salt of quinine used as an antipyretic, antimalarial, antiperiodic, and bitter tonic .
 
 also  esp Brit    
 
Similar sounding terms:   canine  can·non  co·ni·ine  go·ni·on 
 
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