remorseless

from WordNet (r) 3.0 (2006)

remorseless
    adj 1: without mercy or pity; "an act of ruthless ferocity"; "a
           monster of remorseless cruelty" [syn: {pitiless},
           {remorseless}, {ruthless}, {unpitying}]

from The Collaborative International Dictionary of English v.0.48

Remorseless \Re*morse"less\, a.
   Being without remorse; having no pity; hence, destitute of
   sensibility; cruel; insensible to distress; merciless.
   "Remorseless adversaries." --South. "With remorseless
   cruelty." --Milton.
   [1913 Webster]

   Syn: Unpitying; pitiless; relentless; unrelenting;
        implacable; merciless; unmerciful; savage; cruel.
        [1913 Webster] -- {Re*morse"less*ly}, adv. --
        {Re*morse"less*ness}, n.
        [1913 Webster]

from Moby Thesaurus II by Grady Ward, 1.0

47 Moby Thesaurus words for "remorseless":
      bowelless, callous, cruel, dog-eat-dog, flinty, griefless, hard,
      harsh, heartless, impenitent, implacable, inclement, inexorable,
      merciless, pitiless, regretless, relentless, ruthless, savage,
      shameless, sorrowless, unashamed, uncompassionate, uncompassioned,
      uncontrite, unfeeling, unforgiving, ungrieving, unmerciful,
      unpitiful, unpitying, unregretful, unregretting, unrelenting,
      unremitting, unremorseful, unrepentant, unrepining, unrueful,
      unsorrowful, unsorrowing, unsorry, unstoppable, unsympathetic,
      unsympathizing, unyielding, without mercy

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