YF

Gamers use YF as shorthand for "you fail," when trash talking other gamers online. You're likely to encounter this acronym after you screw up, punt a game, or otherwise fail miserably.

Most often, you'll receive YF from ill-mannered opponents, who want to rub their victory and/or your lack of skill in your face. However, in some team games, you may end up receiving YF from your own teammates, if your noob-like actions cause your team to lose a game it otherwise would have won.