burgomaster vs praetor

burgomaster

noun
  • The mayor, or head magistrate, of a town in the Netherlands, Belgium, Germany and certain other countries. 

praetor

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

  • 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 consul in command of the army. 

  • 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. 

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