When you go take a poo that looks normal in the bowl but when you flush the toilet the seemingly solid movement suddenly disintegrates into a brown cloud.
I took a shit that looked like it could choke a donkey but I realized when I flushed that it was just a Hokus Pookus.
Magic words used on the 1980s kids' show Today's Special (a Canadian import which aired on a very early Nickelodeon). The characters would say these words to bring Jeff the mannequin to life.
When a gurl has poop particles in her vagina, often only discovered after you pull out your dick and see the poop on it. usually results in an immediate limp dick.
This often is caused by women who wipe backwards, from back to front, dragging the poop from their ass into their vagina, hence PooPussy.