army vs corps

army

noun
  • A large group of people working toward the same purpose. 

  • Used absolutely for that entire branch of the armed forces. 

  • The governmental agency in charge of a state's army. 

  • A large, highly organized military force, concerned mainly with ground (rather than air or naval) operations. 

  • Within a vast military, a very large tactical contingent (e.g. a number of divisions). 

  • The military as a whole. 

  • Any multitude. 

  • A large group of social animals working toward the same purpose. 

corps

noun
  • An organized group of people united by a common purpose. 

  • A battlefield formation composed of two or more divisions. 

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