Sup sup means supper.

To sup. i.e. To show interest in a member of the opposite sex with verbal expression.

To drink alcohol, usually in yorkshire.

a way of acting ganstah

Completely destroying a person's mental state by either using far more force than necessary to win a competition or taunting them after victory occured.

Work-out supplements that slugs at West Point take three weeks prior to Christmas/Easter/summer break, to aid in their pathetic attempts at increasing their bicep size or getting a 6-pack

Sup is a very nutty word that can be used in greeting one eachother when the person is a tank.

or
Suuuuup, can be used as an expression of excitement.