arbiter vs magister

arbiter

noun
  • A person or object having the power of judging and determining, or ordaining, without control; one whose power of deciding and governing is not limited. 

  • A person appointed, or chosen, by parties to determine a controversy between them; an arbitrator. 

  • A component in circuitry that allocates scarce resources. 

verb
  • To act as arbiter. 

magister

noun
  • The possessor of a master's degree. 

  • Master; sir: a title used in the Middle Ages, given to a person in authority, or to one having a licence from a university to teach philosophy and the liberal arts. 

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