Source : Webster's Revised Unabridged Dictionary (1913)

Workable \Work"a*ble\, a.
   Capable of being worked, or worth working; as, a workable
   mine; workable clay.

Source : WordNet®

workable
     adj : capable of being done with means at hand and circumstances
           as they are [syn: {feasible}, {executable}, {practicable},
            {viable}]