Source : Webster's Revised Unabridged Dictionary (1913)

Convincible \Con*vin"ci*ble\, a.
   1. Capable of being convinced or won over.

   2. Capable of being confuted and disproved by argument;
      refutable. [Obs.] --Sir T. Browne.

Source : WordNet®

convincible
     adj : being susceptible to persuasion [syn: {persuadable}, {persuasible},
            {suasible}]