quinine \qui"nine\, n. f. cf. sp. quinina, fr. sp. quina, or
   quinaquina, peruvian bark, fr. peruv. kina, quina, bark. cf.
   kinic. chem.
   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. written
   also chinine.
   1913 webster
see also:
kinic cinchona calisaya c20h24n2o2 quinia quinina chinine