Source : Webster's Revised Unabridged Dictionary (1913)

Codeine \Co*de"ine\, n. [Gr. ? poppy head: cf. F. cod?ine.]
   (Chem.)
   One of the opium alkaloids; a white crystalline substance,
   {C18H21NO3}, similar to and regarded as a derivative of
   morphine, but much feebler in its action; -- called also
   {codeia}.