The act of losing control in an irational and beast like manner. Often around food and people you dislike.
guy: dude the cafeteria has chili cheese fries
me: im gonna go beast on those fries
Is a term used to describe a teen that didn't just hit puberty, he beat the shit out of it. When a person is called man beast, it is usually because he hit puberty before a lot of other teens.
Person : "Dang dude. You used to be all fat, but now your freakin ripped. Your going man beast! "
6517👍 7823👎