Aggy: Getting angry or violent. It is short for agitated.

I'm getting aggy now!!

Dead Ass: To be completely and honestly serious. A reply used by people who have been questioned on the truth of their comment. To be truthful and not lie. A truncation of the phrase "dead ass serious".

Jackie: "I heard that Amber kissed Jackson!" 

Paige: "No, she isn't in to his type," 

Jackie: "Dude, Dead Ass! It happened."

Dummy: Can be replaced by 'stupid' (can be used in place of dummy, but is not quite as cool)

It's dummy hot outside! 

That was dummy rude, you don't even need to come at me like that.

Man, i'm dummy tired.. 

That test was dummy easy.

Don’t @ me: Don’t come at me

Don't @ me for liking the Kardashians!

Gronking: Violently spiking an object (most common is a football) to the ground in celebration.

Gronking a department store mannequin leg.