An adaptation to STFU, which has included a "fucking" to it. Basically translates to "Shut The Fucking Fuck Up!" Has no real purpose except to emphasize that you want the certain someone(s) to shut up.
by monkeygodkiller August 17, 2007
Jakki: "So I heard this really funny joke yesterday! But... I forgot it. It was really good though."
Calvin: "Dude, stffu, why don't you stop eating so much sugar and go jump off your roof and try to fly"
Calvin: "Dude, stffu, why don't you stop eating so much sugar and go jump off your roof and try to fly"
by Batmanxisxrad October 15, 2008
by JEFF_HARDY_GIRL April 25, 2010