unconcern Meaning, Definition & Usage

  1. noun the trait of remaining calm and seeming not to care; a casual lack of concern
    nonchalance; indifference.
  2. noun a feeling of lack of concern

WordNet

Un`con*cern" noun
Definitions
  1. Want of concern; absence of anxiety; freedom from solicitude; indifference.
    A listless unconcern, Cold, and averting from our neighbor's good. Thomson.

Webster 1913