(n.) Want of curiosity or interest; inattentiveness; indifference.

absentmindedness accidia acedia apathy ataraxia ataraxy carelessness casualness detachment disinterest dispassion disregard disregardfulness distraction easygoingness flightiness flippancy frivolousness giddiness heedlessness inadvertence inadvertency inattention inattentiveness inconsideration indifference indiscrimination inexcitability inobservance insouciance lack of affect lackadaisicalness levity lightmindedness listlessness mindlessness negligence nonchalance nonobservance obliviousness pococurantism recklessness regardlessness shallowness sloth superficiality thoughtlessness unalertness unanxiousness unawareness unconcern unconsciousness unheedfulness unintentiveness unmindfulness unobservance unsolicitousness unwariness unwatchfulness