The Collaborative International Dictionary of English v.0.48:

Barbarism \Bar"ba*rism\ (b[aum]r"b[.a]*r[i^]z'm), n. [L.
   barbarismus, Gr. barbarismo`s; cf. F. barbarisme.]
   1. An uncivilized state or condition; rudeness of manners;
      ignorance of arts, learning, and literature;
      barbarousness. --Prescott.
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   2. A barbarous, cruel, or brutal action; an outrage.
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            A heinous barbarism . . . against the honor of
            marriage.                             --Milton.
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   3. An offense against purity of style or language; any form
      of speech contrary to the pure idioms of a particular
      language. See Solecism.
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            The Greeks were the first that branded a foreign
            term in any of their writers with the odious name of
            barbarism.                            --G. Campbell.
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WordNet (r) 3.0 (2006):

barbarism
    n 1: a brutal barbarous savage act [syn: brutality,
         barbarity, barbarism, savagery]