Source : Webster's Revised Unabridged Dictionary (1913)

Solecism \Sol"e*cism\, n.[F. sol['e]cisme, L. soloecismus, Gr.
   soloikismo`s, fr. soloiki`zein to speak or write incorrectly,
   fr. so`loikos speaking incorrectly, from the corruption of
   the Attic dialect among the Athenian colonists of So`loi in
   Cilicia.]
   1. An impropriety or incongruity of language in the
      combination of words or parts of a sentence; esp.,
      deviation from the idiom of a language or from the rules
      of syntax.

            A barbarism may be in one word; a solecism must be
            of more.                              --Johnson.

   2. Any inconsistency, unfitness, absurdity, or impropriety,
      as in deeds or manners.

            C[ae]sar, by dismissing his guards and retaining his
            power, committed a dangerous solecism in politics.
                                                  --C.
                                                  Middleton.

            The idea of having committed the slightest solecism
            in politeness was agony to him.       --Sir W.
                                                  Scott.

   Syn: Barbarism; impropriety; absurdity.

Source : WordNet®

solecism
     n : a socially awkward or tactless act [syn: {faux pas}, {gaffe},
          {slip}, {gaucherie}]