praetor vs prefect

praetor

noun
  • A consul in command of the army. 

  • An annually-elected curule magistrate, subordinate to the consuls in provincial administration, and who performed some of their duties; numbering initially only one, later two (either of the praetor urbānus (“urban praetor”) or the praetor peregrīnus (“peregrine praetor”)), and eventually eighteen. 

  • A high civic or administrative official, especially a chief magistrate or mayor. Sometimes used as a title. 

  • The title of the chief magistrate, the mayor, and/or the podestà in Palermo, in Verona, and in various other parts of 17th- and 18th-century Italy. 

prefect

noun
  • A commander. 

  • The head of a department in France. 

  • A school pupil in a position of power over other pupils. 

  • An official of Ancient Rome who controlled or superintended a particular command, charge, department, etc. 

  • The head of a county in Albania or Romania. 

  • The head of a prefecture in Japan. 

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