[1] : The Collaborative International Dictionary of English v.0.48

impertinence \imper"tinence\, n. cf. f. impertinence. see
   impertinent.
   1. the condition or quality of being impertinent; absence of
      pertinence, or of adaptedness; irrelevance; unfitness.
      1913 webster

   2. conduct or language unbecoming the person, the society, or
      the circumstances; rudeness; incivility.
      1913 webster

            we should avoid the vexation and impertinence of
            pedants who affect to talk in a language not to be
            understood.                           --swift.
      1913 webster

   3. that which is impertinent; a thing out of place, or of no
      value.
      1913 webster

            there are many subtile impertinences learned in
            schools.                              --watts.
      1913 webster
see also:
impertinent 

[2] : WordNet (r) 2.0

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
see also:
impudence cheek crust gall insolence cheekiness 
freshness perkiness pertness sauciness archness 

[3] : Moby Thesaurus II by Grady Ward, 1.0

73 moby thesaurus words for "impertinence":
   arrogance, audacity, bold front, boldness, brash bearing,
   brashness, brass, brassiness, bravado, brazenfacedness, brazenness,
   bumptiousness, butting-in, cheek, cheekiness, chutzpah, cockiness,
   contempt, contemptuousness, daring, daringness, defial, defiance,
   defying, derision, despite, disassociation, disconnection,
   discourtesy, discreteness, disdain, disjunction, disjuncture,
   disregard, disrespect, disrespectfulness, dissociation, effrontery,
   face of brass, flippancy, forwardness, freshness, gall, hardihood,
   immateriality, impoliteness, impudence, inapplicability,
   inappositeness, incivility, inconnection, inconsequence,
   independence, inquisitiveness, insolence, intermeddling,
   intrusiveness, irrelation, irrelevance, meddlesomeness, meddling,
   nerve, obtrusiveness, officiousness, pertness, presumption,
   presumptuousness, ridicule, rudeness, sauciness, separateness,
   unconnectedness, unrelatedness

Impertinence >> I Words
Impertinence, definition of term: Impertinence
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