The Collaborative International Dictionary of English v.0.48:

Painable \Pain"a*ble\, a. [Cf. F. p['e]nible.]
   Causing pain; painful. [Obs.]
   [1913 Webster]

         The manacles of Astyages were not . . . the less
         weighty and painable for being composed of gold or
         silver.                                  --Evelyn.
   [1913 Webster]