aloofness vs unconcern

aloofness

noun
  • The state of being aloof 

unconcern

noun
  • Lack of interest or care; indifference or apathy. 

  • Freedom from worry or apprehensiveness; insouciance or nonchalance. 

How often have the words aloofness and unconcern occurred in a corpus of books? (source: Google Ngram Viewer )