‘
It is more fun to talk with someone who doesn't use long, difficult words but rather short, easy words like "What about lunch?"’ - Winnie the Pooh.
That sounds great until you start to analyse the words used for different meals in different places. In which case none of the words is 'easy'.
Lunch is a meal usually eaten at midday; it may be light or substantial.
Dinner is usually the main meal of the day and is usually served in the evening . It may also refer to a formal party of people assembled to have a meal together, particularly for a special occasion; a meal given to an animal; or a midday meal (in a context in which the lighter evening meal is called supper).
Supper is a light evening meal; served in early evening (if dinner is at midday) or served late in the evening at bedtime . A supper may also be a social gathering where a light evening meal is served; the evening meal in some dialects of English ; or simply food consumed before going to bed.
Tea is a light mid-afternoon meal of tea and sandwiches or cakes. Sometimes this is called afternoon tea to differentiate it from a main meal (dinner to some people) eaten in the early evening which is often called tea in some areas. "An Englishman would interrupt a war to have his afternoon tea”.
And then there is High Tea - a posh version of afternoon tea, served socially to groups of guests or commercially as a high-priced afternoon cuppa with a menu of gourmet foods.
So here are some typical meal routines:-
Breakfast; lunch; tea; supper.
Breakfast; lunch; afternoon tea; dinner; supper.
Breakfast; dinner; tea; supper.
And so on, ad infinitum....