A trustworthy individual who acts as a middle man between a seller and a network of buyers in black market exchanges, especially those relating to illegal goods. Usually helps facilitate the sale process and is in place to keep the seller (and, consequently, posesser) of the illegal goods from getting set up or screwed over.
Origins: The idea that the fence around the yard keeps the neighbors and cops from looking in and seeing what people are doing.
Fence (on phone to dealer) ~ Yo I got these people who are gonna want a cut, I'll be over in an hour
Dealer ~ Okay man that's $40
Fence ~ okay (calls buyer) I've got your shit, meet me at the Plaza in two hours with $40