The Collaborative International Dictionary of English v.0.48:

Triable \Tri"a*ble\, a. [From Try.]
   1. Fit or possible to be tried; liable to be subjected to
      trial or test. "Experiments triable." --Boyle.
      [1913 Webster]

   2. (Law) Liable to undergo a judicial examination; properly
      coming under the cognizance of a court; as, a cause may be
      triable before one court which is not triable in another.
      [1913 Webster]