When one homosapian mounts another usually in the missonary position. The act commonly dubbed dry humping works best in a state of arousal and when fully clothed to create friction between the groin and crutch area thus creating the sexual act of 'bumping' n 'grinding'.
A reliable source informs me that it is possible to make a male ejaculate through this sexual act alone.

An exclamation made when your friends or family are teasing you to a point where you can't handle it anymore and a hissy fit is in order.

Derived from a YouTube user's famed outburst following Britney's lackluster performance at the 2007 VMA's.