caretaker vs slave-driver

caretaker

noun
  • Someone who takes care of a place or thing; someone looking after a place, or responsible for keeping it in good repair. 

  • Someone who takes care of a person; a parent, carer or other guardian. 

adj
  • Temporary, on a short term basis. 

slave-driver

noun
  • An overseer of slaves at work; a person who puts slaves to work. 

  • An employer who demands excessive amounts of work from employees. 

How often have the words caretaker and slave-driver occurred in a corpus of books? (source: Google Ngram Viewer )