prie-dieu vs tuffet

prie-dieu

noun
  • A piece of furniture on which someone can pray, consisting of a cushioned area to kneel on, with a built-in ledge for books. 

tuffet

noun
  • A large cushion which may have an internal frame, used as a low seat or stool. 

  • An inflatable cushion serving as landing area for precision accuracy parachuting. 

  • A clump of grass or similar vegetation; a small grass-covered mound. 

How often have the words prie-dieu and tuffet occurred in a corpus of books? (source: Google Ngram Viewer )