First letter is--- "S" for Shut
shut it, zip it, silence, be cool, maintain, observe, silencio, shuss, silenz, callate la boca
Second letter is --- " T" meaning The
The used as a determiner. The used as an adverb. The used as a surname. The meaning "enough of".
Third letter is---- "F" meaning Fuck
Used as an intensifier not referring to the verb meaning sexual intercourse in the Anglo-Saxon sense.
Fourth letter is---- "U" meaning Up.
Used as a preposition meaning the direction of travel of your loser jaw in relationship to your upper lip.