This is when refereeing to something that will never happen or has never happened or ever came to be.

It is a spoof off a game called Kingdom Hearts where in the first part of the game you would visit a place called "Traverse Town" which is divided up into 3 districts, Merlins house, a hidden underground, a clock tower, and the 101 Dalmations house. There is no 4th District in Traverse Town, and something is 4th district means it never has been or will be in existence.
"I just toally read the dirtiest comic about Sailor Moon and Tenchi, way 4th District man."

"I liked the story you wrote about him, but I feel it's a bit 4th District since he would never act like that in a situation"
by Sikel Slacker August 28, 2011
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