1. The act of hiding in the bathroom, pretending to take a poop, while engaged in some non-poop related activity such as playing a game on your smartphone or surfing the internet.
2. Spending way more time than needed in the bathroom, playing games or some other waste of time on your phone.
3. Hiding in the bathroom pretending to take a poop in an attempt to avoid some other responsibility.
Hey team, I'm at work but I'm Ghost Pooping so I can get my clan rumble in before time is up.
What's taking Bob so long in the Bathroom? I bet he's ghost pooping and playing Fortnite.
My wife wants me to change the baby's diaper, so I'm ghost pooping instead.