When you are excreting waste from your anus, and you verbally tell your surroundings; when the shit is so bad that it covers the walls, the ground, the ceiling, the mirror, and the children.
The creator, Brian Nho of Windsor Ontario Canada, is an AzN who loves Gangsta rap. Saying shit wasn't good enough for him, so he created a word that could be elongated and was more "gangsta." The word was shiet, and it is pronounced "Sheeeeeeeeeeeeeeeeeeee-it" and often used in the phrase "shiet homey." No real meaning, and hilarious when Asians say it.
Shiet homey dat blond gurl over dur doesn't wanna get up in hurr!