monomaniacal vs purposeful

monomaniacal

adj
  • Fanatical, or obsessed with one cause or idea to the exclusion of other concerns. 

  • Of or relating to a monomaniac. 

purposeful

adj
  • Having a purpose in mind; resolute; determined. 

  • Having purpose; intentional. 

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