noun (n)

• unbiased impartial unconcern(noun.feeling)

  source: wordnet30
• apathy demonstrated by an absence of emotional reactions(noun.feeling)

  Synonym:
  emotionlessness, impassiveness, impassivity, phlegm, stolidity, unemotionality
  

  source: wordnet30
• the trait of lacking enthusiasm for or interest in things generally(noun.attribute)

  Synonym:
  apathy, numbness, spiritlessness
  

  source: wordnet30
• the trait of remaining calm and seeming not to care; a casual lack of concern(noun.attribute)

  Synonym:
  nonchalance, unconcern
  

  source: wordnet30
• The quality or state of being indifferent, or not making a difference; want of sufficient importance to constitute a difference; absence of weight; insignificance.(noun)

  source: webster1913