A statement of defiant dismissal that one gives to one's haters.
Tupac once said, "Fuck all y'all."
When you get pissed about someone's opinion or advice you didn't ask for.
1.Friend: "You know smoking crack is a occupational hazzard"
2.You: "Oh? That's what the last Muthafuka said, But I didn't ask for your advice so Fuck All, Fuck Y'all! "