Dead. This comes from how fish float up to the surface "belly up" when they die
one of my goldfish went belly up last night, now I have to flush it.
by butterfly on the wall January 12, 2010
Slang term in the metro st. louis/illinois area that refers to something in Belleville; a Belleville hot spot or scene.
Tonight we're going "belly-up" at the Belleville skate park.
by Baby Face Jonas August 30, 2007