Conjoins the two following acronyms 'stfd' and 'stfu'

"Sit the fuck down, and shut the FUCK UP!"

Used when 'stfd' or 'stfu' doesn't achieve a satisfactory effect.

Often used to establish superiority and 1337ness.
"stfd and stfu bitch and gtfo you n00b"
Mr. Pub-Star 1337
by I_Love_hooters January 4, 2005
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