The word supper is annoying

Haha it's a southern thing.
My family uses it all the time

Does it mean dinner?

Yes supper is another word for dinner in the south

Same

:)

?
It's "Dinner" that's ambiguous, it could either be supper or lunch.(dinner time)

Dinnertime definition
dinnertime (countable and uncountable, plural dinnertimes) The time when dinner takes place. The time when dinner is ready. (Britain) The midday break in English schools (some areas), lunchtime. The dinner hour, the hour between 6 and 7 p.m.

Interesting :)