SYFFUF 

SYFFUF is short for "Shut your fucking face, uncle fucker", a commonly used phrase in the USA. It was introduced in 1890 by Pope Gregorius XIV but gained popularity when Matt Stone and Trey Parker used it for a song in their popular television series "South Park".

Aunt: "Bob, you suck!"
Bob: "SYFFUF!"

SYFFUF by Burn666 January 17, 2008

Syffuf 

An abbreviation for the term "Shut your fucking face uncle fucka"

Terrence sent the text "syffuf" to Phillip

Syffuf by SUPERWOGFAN100 September 7, 2025

syffu 

Shut your fucking face up.

<CraBYbebeq> u WÝLL die while u r sexing and speaking abt SEX...omg GET LOST THE WORLD!!
<Requiett> Syffu.

syffu by Requiett November 13, 2004