mastership vs skillage

mastership

noun
  • Mastery: superior skill. 

  • Mastery: dominion, superiority, control. 

  • The state or office of a master. 

  • A title of respect, sometimes ironic. 

skillage

noun
  • The state of being highly skilled, the state of being skillful. 

  • The differentiating, or skilling, of call distribution based on an individual's skill level, expertise, or training. 

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