The feeling caused by holding in a fart, that results in the poop being carbonated with the unpassed gas. The resulting poop is bubbly and airy, and often painful to excrete.
Man, I've been holding in so many farts that I'm getting fecal carbonation!
My asshole just got torn apart by my shit's fecal carbonation.
a drink from burger king that oddly resembles a coke
Guy: "Oh my god is this coke from Burger King"
Same Guy: *sips the drink and then realizes what it is*
That same guy:"Oh what is that? That's carbonated poop water."