fantasy vs oral tradition

fantasy

noun
  • That which comes from one's imagination. 

  • A fantastical design. 

  • The drug gamma-hydroxybutyric acid. 

  • The literary genre generally dealing with themes of magic and the supernatural, imaginary worlds and creatures, etc. 

verb
  • To imagine; to conceive mentally. 

  • To fantasize (about). 

oral tradition

noun
  • Cultural material transmitted orally from one generation to another. 

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