bursar vs changer

bursar

noun
  • A student funded by a bursary. 

  • The treasurer of a university, college or school. 

changer

noun
  • A person employed in changing or discounting money. 

  • Someone or something who changes things. 

  • Someone or something that changes or transforms itself. 

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