afternoon tea vs mealtime

afternoon tea

noun
  • A small meal or snack eaten between lunch and dinner (supper); a period of time set aside for this purpose, taken as a break from work or from a conference. 

  • A formal afternoon meal comprising light snacks, accompanied by tea. 

mealtime

noun
  • The appointed time at which a meal is served or eaten. 

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