The most common names I've seen for a poker joint are: Poker Club... Poker Room... Poker Parlor...
Poker Lounge... Poker Place... Poker House... even: Poker Den... Poker Barn... Poker Depot... Poker Shack
and Poker Palladium!

But the most royal name of them all has to be "Poker Palace"... here are a few examples:

Scans 29, 30, 31 & 32 are courtesy of the ChipGuide.