niceness vs virulence

niceness

noun
  • A value determining how much processor time to concede to a running process. (See also nice (verb), renice.) 

  • Effeminacy; indulgence in soft living or luxuriousness. 

  • Fastidiousness; fine sensitivity. 

  • Pleasantness, especially of behaviour or personality; agreeableness. 

virulence

noun
  • A measure of how virulent a thing is. 

  • The state of being virulent. 

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