when a girl is passed out at a party you drag her into the laundry room, then you pull down your pants stand over her face then pour cold water on her face then she will sit up quickly, right into your ballsack. her ice cold face will give the sensation of a waterfall.

When you hear a guy pissing in a toilet while he's standing up (Which makes a "waterfall" sound). When you DO hear a waterfall, scream "WATERFALL!!!"

The act of dragging your fingers vertically down another person's face as seen in the movie Face/Off

A beaver waterfall is when a woman lies down in the bathtub, places both legs on the wall, places her vagina underneath the faucet, and uses running water to masterbate.

An urban waterfall is a natural waterfall located in an urban area that has some man-made changes done to it, such as enclosing the natural creek above or below the falls into a storm sewer or box culvert or the construction of a bridge or road over the creek above the falls. The actual waterfall itself normally has not changed, just its natural surroundings have been changed by man.

To get that pussy like a slip n slide, also a hot song by the one and only Ludacris

When one person in a group checks their smartphone and incites a domino effect of everybody else checking their own phones, thus ending all live discussion.