supply teacher vs trainer

supply teacher

noun
  • A teacher who fills a temporary position in a school on a short-term basis; often supplied by an agency. 

trainer

noun
  • A person who trains another; a coach. 

  • A person responsible for treating injuries sustained by players during matches; a physiotherapist. 

  • A patch for a video game that applies cheats. 

  • A running shoe or sneaker. 

  • A piece of indoor equipment allowing a bicycle to be ridden while stationary. 

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