criminal vs robber

criminal

noun
  • A person who is guilty of a crime, notably breaking the law. 

adj
  • Against the law; forbidden by law. 

  • Guilty of breaking the law. 

  • Abhorrent or very undesirable. 

  • Of or relating to crime or penal law. 

robber

noun
  • A person who robs. 

  • An animal who robs. 

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