acrimoniousness acrimoniousness /ˌækrɪˈmoʊniəsnɪs/

noun

1. A feeling of deep and bitter anger and ill-will  ( gall , rancour [Canadian, British] , acrimoniousness , hard feelings , bitterness , rancor [American] , resentment , ill feeling )
   a feeling of deep and bitter anger and ill-will
    The bitterness in her voice betrayed the deep hurt she had experienced.
   The bitterness in her voice betrayed the deep hurt she had experienced.