The Collaborative International Dictionary of English v.0.48:

Brutality \Bru*tal"i*ty\, n.; pl. Brutalities. [Cf. F.
   brutalit['e].]
   1. The quality of being brutal; inhumanity; savageness;
      pitilessness.
      [1913 Webster]

   2. An inhuman act.
      [1913 Webster]

            The . . . brutalities exercised in war. --Brougham.
      [1913 Webster]

WordNet (r) 3.0 (2006):

brutality
    n 1: the trait of extreme cruelty [syn: ferociousness,
         brutality, viciousness, savagery]
    2: a brutal barbarous savage act [syn: brutality, barbarity,
       barbarism, savagery]