demonstrator vs trainer

demonstrator

noun
  • An assistant to a lecturer. 

  • The forefinger. 

  • One who demonstrates anything, or proves beyond doubt. 

  • An item, particularly a vehicle, used in demonstrations to a customer or user. 

  • One who demonstrates products in a retail environment; a merchandiser. 

  • One who teaches anatomy from the dissected parts. 

  • One who takes part in a demonstration; a protester. 

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 demonstrator and trainer occurred in a corpus of books? (source: Google Ngram Viewer )