enigmatic vs nondescribable

enigmatic

adj

  • Defying description. 

  • Pertaining to an enigma. 

  • Mysterious. 

  • Enigmatical. 

nondescribable

adj

  • Not describable; incapable of being described. 

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