The gambling ship is just called a gambling ship; it doesn't have any other name.
It is registered in a small country atop the Caribbean Sea, where the gambling industry is legal.
According to the "United Nations Convention on the Law of the Sea," it is subject only to the laws of the country of registration, thus it can cruise the high seas year-round. As long as it turns into an ordinary cruise ship when entering the waters of a country, it can dock freely.
Of course, it doesn't dock easily, and except for maintenance, it hardly ever leaves international waters.
It operates on a membership basis; anyone who spends ten thousand US dollars on a ticket can become a temporary member for one night of extravagant gambling on board.
This might sound easy, but this single requirement eliminates ninety percent of the people in the world.
Because land-based casinos don't charge an entry fee, and sometimes give out money during holidays and promotions.