pooo Share definition Flag This spelling is used to express the amount of shit that they pass. If this were to be pronounced, it would have an extention of "o"s. This would give meaning to how much they have passed. For a big shit it would be "I just done a Pooooo" pooo by Cheyne January 25, 2004 0 0 Get merch Get the pooo mug. Buy Now — $32.95 See more merch