Masters vs magistrate

Masters

noun
  • A master's degree. 

  • A person holding a master's degree, as a title. 

name
  • A surname originating as an occupation 

magistrate

noun
  • A master's degree. 

  • A comparable official in medieval or modern institutions. 

  • A judicial officer with limited authority to administer and enforce the law. A magistrate's court may have jurisdiction in civil or criminal cases, or both. 

  • A high official of the state or a municipality in ancient Greece or Rome. 

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