1. A statement used to indicate you have to poop.
2. Declaring you have to poop by using reference to baseball, the next batter up is the on deck batter.
3. A proclimation that the next thing you are going to do is poop. Usually expressed with a sense of urgency.
1. Are we almost home? I have a poop on deck that cannot wait much longer.
2. He wanted to go home with the girl from the bar but he had a poop on deck and knew it would ruin his evening.
Notes:Not to be confused with Poop Deck.