president vs proconsul

president

noun
  • The head of state of a republic. 

  • Primary leader of a corporation. Not to be confused with CEO, which is a related but separate position that is sometimes held by a different person. 

  • In presidential republics, the head of government and head of state. 

  • A person presiding over a meeting; a chair, presiding officer, presider. 

verb
  • To act as president; to do presidential duties. 

proconsul

noun
  • A magistrate who served as a consul and then as the governor of a province. 

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