aide-de-camp vs burghmaster

aide-de-camp

noun
  • A military officer who serves as an adjutant to a higher-ranking officer, prince or other high political dignitary. 

burghmaster

noun
  • An officer who directs and lays out the meres or boundaries for the workers. 

  • A burgomaster. 

How often have the words aide-de-camp and burghmaster occurred in a corpus of books? (source: Google Ngram Viewer )