An abbreviation for "she wants to fuck you." Usually uttered from one bro to another bro after a girl has shown her hand.
Guy 1 to Guy 2: "So I'm visiting my brother at NYU this weekend and we signed up for a pong tournament. Cash prize for first place is $200."
Random Chick 1: "Oh my gosh! Good luck!"
Guy 2 to Guy 1: "S.W.T.F.Y., dude."
Guy 1 to Guy 2: "Truth."
Random Chick 1: "Oh my gosh! Good luck!"
Guy 2 to Guy 1: "S.W.T.F.Y., dude."
Guy 1 to Guy 2: "Truth."
by stickitinplease October 29, 2010
Get the S.W.T.F.Y.mug.