The quality of being distasteful; the state of being unpleasant, offensive, or causing disapproval.
From 'distasteful' (dis- + taste + -ful) + '-ness' suffix forming an abstract noun from an adjective.
The 'distastefulness' of historical atrocities lies not just in what happened but in how deliberately cruel and offensive the actions were—the word captures that compounded disgust.
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