Source : Webster's Revised Unabridged Dictionary (1913)

Impertinence \Im*per"ti*nence\, n. [Cf. F. impertinence. See
   {Impertinent}.]
   1. The condition or quality of being impertnent; absence of
      pertinence, or of adaptedness; irrelevance; unfitness.

   2. Conduct or language unbecoming the person, the society, or
      the circumstances; rudeness; incivility.

            We should avoid the vexation and impertinence of
            pedants who affect to talk in a language not to be
            understood.                           --Swift.

   3. That which is impertinent; a thing out of place, or of no
      value.

            There are many subtile impertinences learned in
            schools.                              --Watts.

Source : WordNet®

impertinence
     n 1: an impudent statement [syn: {impudence}, {cheek}]
     2: the trait of being rude and impertinent; inclined to take
        liberties [syn: {crust}, {gall}, {impudence}, {insolence},
         {cheekiness}, {freshness}]
     3: inappropriate playfulness [syn: {perkiness}, {pertness}, {sauciness},
         {archness}]