YOU'RE A POOPY HEAD comes from a youtuber called "angry video game nerd" with the words "YOU'RE A POOPY HEAD! DO WE NEED TO SPELL IT OUT?! YOUR A POOPY HEAD!" and thus creating an internet legend
An insult used by people under the age of 8. It is used when a child calls someone a "Poopy Head" It is also used in a joking manner by people over the age of 8. The word "Poopy Head" is basically "Sh*t Head" but for toddlers.
Billy: Horses don't have hooves until the farmer nails them on.
Jack: So, what do they have before that?
Billy: Feet?
Jack: ... You're slow in the head like a big pizza pie!
Slang from the south that entails whatever you are about to do is probably not going to be in your best interest. Rarely actually used in favor of other phrases, and typically only said by older folks.
Person 1: "I haven't practiced in a few years, but I'm pretty sure I can still backflip."
Person 2: "Go ahead, if you're bad."