Source : Webster's Revised Unabridged Dictionary (1913)

Confutable \Con*fut"a*ble\, a.
   That may be confuted.

         A conceit . . . confutable by daily experience. --Sir
                                                  T.Browne.

Source : WordNet®

confutable
     adj : able to be refuted [syn: {questionable}, {refutable}, {confutative}]