Source : Webster's Revised Unabridged Dictionary (1913)

Emetic \E*met"ic\, a. [L. emeticus, Gr. ?, fr. ? to vomit, akin
   to L. vomere: cf. F. ['e]m['e]tique. See {Vomit}.] (Med.)
   Inducing to vomit; exciting the stomach to discharge its
   contents by the mouth. -- n. A medicine which causes
   vomiting.

Source : WordNet®

emetic
     n : a medicine that induces nausea and vomiting [syn: {vomit}, {vomitive},
          {nauseant}]