WordNet (r) 3.0 (2006):

torturing
    adj 1: extremely painful [syn: agonizing, agonising,
           excruciating, harrowing, torturing, torturous,
           torturesome]
    n 1: the deliberate, systematic, or wanton infliction of
         physical or mental suffering by one or more persons in an
         attempt to force another person to yield information or to
         make a confession or for any other reason; "it required
         unnatural torturing to extract a confession" [syn:
         torture, torturing]

Moby Thesaurus II by Grady Ward, 1.0:

44 Moby Thesaurus words for "torturing":
   abuse of terms, agonizing, catachresis, contorting, corruption,
   distortion, eisegesis, error, false coloring, garbling, gloss,
   harrowing, malentendu, malobservation, misapplication,
   misapprehension, miscitation, misconception, misconstruction,
   misdirection, misexplanation, misexplication, misexposition,
   misintelligence, misinterpretation, misjudgment, misquotation,
   misreading, misrendering, misrepresentation, mistranslation,
   misunderstanding, misuse, misuse of words, perversion, racking,
   slanting, squeezing, straining, tearing, tormenting, torturous,
   twisting, wrenching