WordWeb Online

1. Used of the degree of something undesirable e.g. pain or weather
   - badness, severity
    
2. The quality of being hard to endure, uninviting or formidable
   "the severeness of northern winters";
   - asperity, grimness, hardship, rigor [US], rigour [Brit, Cdn], severity, rigorousness, rigourousness [Brit, non-standard]
    
3. Extreme plainness
   - austereness, severity
    
4. Excessive sternness
   "severeness of character";
   - severity, harshness, rigor [US], rigour [Brit, Cdn], rigorousness, rigourousness [Brit, non-standard], inclemency, hardness, stiffness

Type of: difficultness, difficulty, intensity, intensiveness, plainness, sternness, strictness