People in utah use this word...and it actually means to ditch

the whale tail is the shape formed when a g-string rides up high over a womans trousers

To skip school or any school-related activity, like school assembly.

Noun. The snow that is set into movement when snowboarding or skiing in steep terrain (above 40 degrees). Due to the often loose cohesion of the powders top layer, more snow can be accumulated by the already moving snow. If the slope is sufficiently steep for a a couple hundred meters, the sluff can get very fast. One turn on top of a steep face can cause a sluff that reaches avalanche-like proportions.

A relatively small sluff can knock a snowboarder/skier off his feet and take him for a fast and dangerous ride down to the end of the slope or over a cliff.

Sluff is one of the mayor difficulties in big mountain snowboarding/skiing, yet it also presents an interesting challenge and is very spectacular to watch. The techniques to deal with sluff while riding are called sluff management.

To skip school, or ditch class

A sluff is a short, little, ugly ,fat, fucker.

Used most commonly in the Western U.S., sluffing (probably derived from the word 'to slough') is synonymous with skipping class, cutting class, or ditching class.