An acronym for Shut The Fuck Up. The illiterate mass that uses this seems to conveniently fail to realize that acronyms do not include a "T" for the article "the".
"If you ain't got nothing nice to say, then STFU."
"That's a double-negative."
"Huh, why do you speak in gibberish?"
"That's a double-negative."
"Huh, why do you speak in gibberish?"
by Killa Clownz November 06, 2008