cafeteria vs dining room

cafeteria

noun
  • A dining area in an institution where meals may be purchased (as above), provided, or brought in from elsewhere. 

  • A restaurant in which customers select their food at a counter then carry it on a tray to a table to eat. 

dining room

noun
  • A room, in a home or hotel, where meals are eaten. Some restaurants provide private dining rooms for hire, away from the main public eating areas. 

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