What's the Poop?

Allison: What does poop mean?
Me: Poop? It's what comes out when you go to the bathroom.
Sarah: Solid waste!
Allison: No! Not that kind of poop. The other kind of poop.
Me: What other kind of poop?
Allison: Like when you're tired?
Me: Oh! Pooped! Yeah, it means tired.