US terminology question

[bluespirit]

A query for my US flisters please.
Is it more usual to refer to waiters/waitresses as that or are they servers? Or are the terms interchangeable?
It's actually from Rodney's pov but I'm assuming the US & Canada will be similar?

Thanks! ♥

EDIT: Thanks for all the replies. I think I'm sorted now. I have the best flist ever.
*hugs*