two meanings both the most accurate!
1. its pc (pollitically correct) and also a dyslexic's p.o.v of the word gay (as in omo-sexwal, not the happy kind, you know faeries?) so say it you'll feel like a ninja when you realize that the person has no idea what your saying (note to self (yag=gay bassackwards!)
2. its the abbreviated form of Y.ou A.re G.ay and its meaning gay as in sf flamboyant castro district hits on you gay not happy
1. tom" you think i'm weird for watching a chik flik by myself?"
jen" bro your yag!"
2. tom" you really think im yag?"
jen" no i don't just think i i know Y.A.G.