(Ha, an Australian should talk!)
For instance, here, the most common terms for the three meals of the day are:
Morning - Breakfast (or Brekky)...lol
Midday - Lunch (no other term I'm aware of)
Evening - Tea (believe it or not. We know that tea is a beverage but for some reason most of us call this meal "Tea" although "Dinner" is also used.
As far as "Supper" is concerned, well, I don't think I've ever heard an Australian use the term except when describing Leonardos wonderful painting (or talking about that first "Christian version of Passover" which of course is the subject of the painting).
As for calling Lunch (midday meal) Dinner, well, that must be a British thing.
I'm aware of many, many terms that are used here that no-one would ever have heard of, but that's unfair, especailly as we are well known for our 'unique' and 'cryptic' way of speaking.
I would , however, be interested in hearing about some of the 'unusual' terms that you other people have for one thing or another.

