Lunch is the noon meal of the day... small with 2 courses
Supper is the evening meal of the day... small with 2 courses
Dinner may be served anytime from noon on and is the larger meal. with up to 7 courses.
For example... I serve Thanksgiving dinner would be called Dinner even if it was served at noon!!
end of etiquette lesson ya'll - I think we tend to call it what ever we like....