That seems to sum up how it is used most of the time. But, it seems a bit fluid, e.g., when I was a kid, school cafeteria lunches were almost all hot meals. Later that day, we would have dinner.I remember reading somewhere the "official" definition.
If you eat your big meal of the day at noon, that's dinner. What you eat that evening would be supper. If you eat lunch at noon, your evening meal is dinner.
YMMV