In mathematics, the Klein Bottle is a certain non-orientable surface, i.e. a surface (a two-dimensional topological space), for which there is no distinction between the "inside" and the "outside" of the surface. Its inside is its outside. It contains itself. A Klein bottle is a theoretical entity that exists only in 4 dimensions.

A Klein Asshole, aka Kleinhole, is someone who's assholishness has engulfed them to such a degree that it is no longer possible to tell where the Asshole begins or ends. As opposed to the Klein Bottle, Klein Assholes are very real and exist in 3 dimensions and are all around us.

A drug slang term used to describe a cociane and ketamine combination. The term originated from the new york dance scene back in the day.

Inserting the index finger into an unsuspecting subjects butt hole and shouting "Poo finger". Laughter usually follows the poofinger, except the subject who is left mildly disgusted and scarred.

To have a 6 and 9 in your hole cards in texas hold'em.

The act of fucking someone in the ass, then after pulling out, dropping a nickel into the newly expanded hole.