WordWeb Online

1. The quality of being ghastly
   - ghastliness, gruesomeness, luridness
    
2. The quality of being hard to endure, uninviting or formidable
   "the grimness of northern winters";
   - asperity, hardship, rigor [US], rigour [Brit, Cdn], severity, severeness, rigorousness, rigourousness [Brit, non-standard]

Type of: difficultness, difficulty, fix [informal], frightfulness, hole [informal], jam [informal], kettle of fish [informal], mess [informal], muddle [informal], pickle [informal]