aficionado vs past master

aficionado

noun
  • A person who likes, knows about, and appreciates a particular interest or activity (originally bullfighting); a fan or devotee. 

past master

noun
  • One who has an extremely high level of ability or knowledge within an area of achievement or expertise. 

  • Someone who has previously been a master at a given lodge. 

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