mealtime vs square meal

mealtime

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

square meal

noun
  • A (nutritionally) complete and satisfying meal, especially one suitable for a person performing physical labour. 

  • Used other than figuratively or idiomatically: see square, meal. 

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