The love child of "yo" and "so". Used to catch a peer's attention when one is about to say something important. Often capitalized when the shock factor of what the speaker is saying exceeds lowercase letters, becoming YOSO! When one is expressing concern or wary, they might draw the letters out to resemble "yooooossooooo". Derived from the popular comedy duo Jake and Amir. May also be used as a greeting between two friends.
Nicole: Yoso my cat threw up in the bong water.
Diana: Ugh, tits.
Amir: Yoso, when it snows my feet, they bleed coz my shoes have holes and I can nay afford socks'o.
Randall: YOSO PARTY AT MY PLACE TONIGHT!
Friend #1: Yoso
Friend#2: Yooosoooo I have a test tomorrow and I'm not ready!