adjutant vs aide-de-camp

adjutant

noun
  • A lower-ranking officer who assists a higher-ranking officer with administrative affairs. 

  • Any bird of the genus Leptoptilos, a branch of the stork family (Ciconiidae) native to India and Southeast Asia. 

  • An assistant. 

adj
  • Assistant; who helps a higher-ranking officer. 

aide-de-camp

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

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