There's two different versions in my life. Here at home, the meals are known as:
Breakfast, lunch, tea. We don't snack in between, the parents and DH just have lots of drinks in between, but, I almost never do.
At the nursery, for the kids it's:
Breakfast, snack, dinner, snack, tea. The employees get a 15 min break, and a 45 min "dinner".
My packed lunch is a "sarnie"(which I thought meant sardines, which, of course, it doesn't) with a "piece of" fruit, and sometimes some sort of cake or biscuit, when I can be bothered at 5am to remember to take something like that, and a canned drink.