ruthlessness

ruthlessness
    n 1: mercilessness characterized by a lack of pity [syn:
         {pitilessness}, {ruthlessness}]
    2: feelings of extreme heartlessness [syn: {cruelty},
       {mercilessness}, {pitilessness}, {ruthlessness}]
    

Ruthless \Ruth"less\, a.
   Having no ruth; cruel; pitiless.
   [1913 Webster]

         Their rage the hostile bands restrain,
         All but the ruthless monarch of the main. --Pope.
   [1913 Webster] -- {Ruth"less*ly}, adv. -- {Ruth"less*ness},
   n.
   [1913 Webster]
    

51 Moby Thesaurus words for "ruthlessness":
      animality, atrociousness, barbarity, barbarousness, beastliness,
      bestiality, bloodiness, bloodlust, bloodthirst, bloodthirstiness,
      bloody-mindedness, brutality, brutalness, brutishness, cannibalism,
      cruelness, cruelty, ferociousness, ferocity, fiendishness,
      fierceness, flintiness, hardness, harshness, heartlessness,
      inclemency, inexorableness, inhumaneness, inhumanity,
      mercilessness, pitilessness, relentlessness, remorselessness,
      sadism, sadistic cruelty, sanguineousness, savagery, short shrift,
      tender mercies, truculence, uncompassionateness, unfeelingness,
      unforgivingness, unmercifulness, unremorsefulness,
      unsympatheticness, unyieldingness, vandalism, viciousness,
      violence, wanton cruelty