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

unconcern \un`concern"\, n.
   want of concern; absence of anxiety; freedom from solicitude;
   indifference.
   1913 webster

         a listless unconcern,
         cold, and averting from our neighbor's good. --thomson.
   1913 webster

[2] : WordNet (r) 2.0

unconcern
     n 1: the trait of remaining calm and seeming not to care; a
          casual lack of concern syn: nonchalance, indifference
     2: a feeling of lack of concern ant: concern
see also:
nonchalance indifference concern 

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

83 moby thesaurus words for "unconcern":
   accidia, acedia, aloofness, apathy, ataraxia, ataraxy,
   benumbedness, blah, blahs, boredom, carelessness, casualness,
   comatoseness, detachment, disinterest, disinterestedness,
   dispassion, disregard, disregardfulness, dullness, easygoingness,
   heartlessness, hebetude, heedlessness, hopelessness, impassiveness,
   impassivity, inappetence, inattention, incuriosity, incuriousness,
   indifference, indifferentism, indifferentness, indiscrimination,
   inexcitability, insouciance, intellectual inertia, lack of affect,
   lack of appetite, lack of interest, lackadaisicalness, languidness,
   lassitude, lethargicalness, lethargy, listlessness, mindlessness,
   negligence, nonchalance, numbness, offhandedness, passiveness,
   passivity, phlegm, phlegmaticalness, phlegmaticness, plucklessness,
   pococurantism, recklessness, regardlessness, resignation,
   resignedness, sloth, sluggishness, sopor, soporifousness,
   spiritlessness, spunklessness, stolidity, stupefaction, stupor,
   supineness, torpidity, torpidness, torpor, unanxiousness,
   uninquisitiveness, uninterestedness, unmindfulness,
   unsolicitousness, withdrawal, withdrawnness

Unconcern >> U Words
Unconcern, definition of term: Unconcern
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