free spirit vs kook

free spirit

noun
  • One who is a nonconformist or who does not recognize the authority of others. 

  • A member of the organized heretic movement Brethren of the Free Spirit in opposition of the Catholic Church from the 13th to 15th centuries. 

kook

noun
  • An eccentric, strange or crazy person. 

  • A boardsport participant who lacks style or skill; a newbie who acts as if they are better at the sport than they are. 

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