instructorship vs tuition

instructorship

noun
  • The office of an instructor 

  • the term of this office 

tuition

noun
  • The training or instruction provided by a teacher or tutor. 

  • A sum of money paid for instruction (such as in a high school, boarding school, university, or college). 

  • Paid private classes taken outside of formal education; tutoring. (also used attributively) 

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