POO-merr-ang. Noun. Primarily used in corporate office environments involving the distribution of poo. Not to be confused with poo that rolls uphill or downhill, the poomerang is poo that is sent but inevitably returns at much higher velocity to its original vendor.
After you have a bowel movement, and you think everything has gone down, one little piece of poo will come floating back into the bowl. Since it has come back, it is a poo-merang.
Firing a shit out of your ass that wizzes through the air and then returns to you. This is then used as a gift to be used as a play thing for little Austrailian children or any other kind of child that enjoys outdoor play.
When you boomerang (TM) your poop so it looks like you have ultimate colon-sphincter coordination and can suck the turtle head back inside after its poked out.