pensionary vs senior

pensionary

noun
  • A leading functionary and legal adviser of the principal town corporations in the Netherlands. 

  • one who receives a pension; a pensioner 

adj
  • pertaining to a pension 

  • maintained by a pension; receiving a pension 

senior

noun
  • Somebody who is higher in rank, dignity, or office. 

  • A final-year student at a high school or university. 

  • Someone seen as deserving respect or reverence because of their age. 

  • An old person. 

  • Someone older than someone else (with possessive). 

adj
  • Older; superior 

  • Higher in rank, dignity, or office. 

  • Of or pertaining to a student's final academic year at a high school (twelfth grade) or university. 

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