expert vs initiate

expert

noun
  • A person with extensive knowledge or ability in a given subject. 

  • A player ranking just below master. 

adj
  • Extraordinarily capable or knowledgeable. 

  • Characteristic of an expert. 

initiate

noun
  • One who is oriented in and familiar with a topic or subject; especially, one who is an expert in it. 

  • A new member of an organization. 

  • One who has been through a ceremony of initiation. 

verb
  • To instruct in the rudiments or principles; to introduce. 

  • To do the first act; to perform the first rite; to take the initiative. 

  • To confer membership on; especially, to admit to a secret order with mysterious rites or ceremonies. 

  • To begin; to start. 

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