hangi vs hibachi

hangi

noun
  • Food cooked in this way. 

  • A traditional Māori method of cooking food using heated rocks buried in a pit oven. 

hibachi

noun
  • The griddle used in such cuisine; teppan. 

  • A cooking method and performance art in which the chef grills pieces of food on a hot metal griddle in front of the guests; teppanyaki. This terminology is virtually unknown in Japan. 

  • A portable brazier, powered by charcoal, used for cooking. 

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