Pronounced "SIFT". Acronym for Shut Your Fucking Trap.
Monica - "Hey Chandler, have you picked up your dirty underpants off the kitchen floor yet, you rancid fart?"
Chandler - "Syft, Whore."

Excerpt from "The One Where Chandler And Monica Have A Row But Make Up By The End"
by mockschmock December 13, 2006
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