Source : Webster's Revised Unabridged Dictionary (1913)

Teachable \Teach"a*ble\, a.
   Capable of being taught; apt to learn; also, willing to
   receive instruction; docile.

         We ought to bring our minds free, unbiased, and
         teachable, to learn our religion from the Word of God.
                                                  --I. Watts.

Source : WordNet®

teachable
     adj : ready and willing to be taught; "docile pupils eager for
           instruction"; "teachable youngsters" [syn: {docile}]