Racking

from WordNet (r) 3.0 (2006)

racking
    adj 1: causing great physical or mental suffering; "a wrenching
           pain" [syn: {racking}, {wrenching}]

from The Collaborative International Dictionary of English v.0.48

Rack \Rack\, v. i. [imp. & p. p. {Racked} (r[a^]kt); p. pr. &
   vb. n. {Racking}.] [See {Rack} that which stretches, or
   {Rock}, v.]
   To amble fast, causing a rocking or swaying motion of the
   body; to pace; -- said of a horse. --Fuller.
   [1913 Webster]

from The Collaborative International Dictionary of English v.0.48

Racking \Rack"ing\, n. (Naut.)
   Spun yarn used in racking ropes.
   [1913 Webster]

from Moby Thesaurus II by Grady Ward, 1.0

46 Moby Thesaurus words for "racking":
      acute, afflictive, agonizing, atrocious, barbarous, biting,
      consuming, cramping, cruel, desolating, distressing, excruciating,
      ferocious, fierce, gnawing, grave, griping, hard, harrowing, harsh,
      heartbreaking, heartrending, heartsickening, heartwounding,
      hurtful, hurting, inhuman, painful, paroxysmal, piercing, poignant,
      pungent, rending, savage, severe, sharp, shooting, spasmatic,
      spasmic, spasmodic, stabbing, stinging, tearing, tormenting,
      torturing, torturous

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