hardy vs tough cookie

hardy

noun
  • Anything, especially a plant, that is hardy. 

  • A blacksmith's fuller or chisel, having a square shank for insertion into a square hole in an anvil, called the hardy hole. 

adj
  • Impudent. 

  • Having rugged physical strength; inured to fatigue or hardships. 

  • Able to survive adverse growing conditions. 

  • Brave and resolute. 

tough cookie

noun
  • A hardy, resilient animal or plant. 

  • Something troublesome or difficult to handle. 

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

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