bluffing vs make-believe

bluffing

noun
  • A bluff; a false expression of the strength of one's position in order to intimidate. 

make-believe

noun
  • The quality or act of pretending; acting as if something is true when in fact one knows it is not. 

  • The action of pretending or imagining that things are better than they really are. 

How often have the words bluffing and make-believe occurred in a corpus of books? (source: Google Ngram Viewer )