Source : Webster's Revised Unabridged Dictionary (1913)

Torturous \Tor"tur*ous\, a.
   Involving, or pertaining to, torture. [R.] ``The torturous
   crucifixion.'' --I. Disraeli.

Source : WordNet®

torturous
     adj : extremely painful [syn: {agonizing}, {agonising}, {excruciating},
            {harrowing}, {torturing}, {torturesome}]