enemy vs tough cookie

enemy

noun
  • Someone who is hostile to, feels hatred towards, opposes the interests of, or intends injury to someone else. 

  • A hostile force or nation; a fighting member of such a force or nation. 

  • Something harmful or threatening to another 

  • Of, by, relating to, or belonging to an enemy. 

  • A non-player character that tries to harm the player. 

verb
  • To make an enemy of. 

tough cookie

noun
  • A person who can endure physical or mental hardship; a hardened, strong-willed person. 

  • A hardy, resilient animal or plant. 

  • Something troublesome or difficult to handle. 

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