This is an abbreviation for: "You Suck At Life"
Hey Dexter! YSAL! You (really) Suck At Life! And you smell like poo too!
by Humpty Dizzle February 02, 2006
Acronym for "You Suck At Life" which is an offensive comment that can be used in almost any negative context but most often used as a replacement for calling someone a loser.
You got dumped again?!? YSAL man.
by Funmunke July 12, 2013