Speshul is what Sues are. It is related to 'special' in the same way that urple is related to purple. Speshulness is overpowering, over the top, and overwhelmingly irritating. To use the word speshul to describe a character or an object conveys the user's complete and utter contempt for the character/object. Often, magical jewellery that no explanation exists for is described as speshul.
Things that are speshul are often also coloured using the colours of the Sue Colour Spectrum. They may also be shiny.
Speshul characters are generally hard to defeat in a direct confrontation because they are the best at everything. However, as they often lack any kind of imagination, or even a brain, they can be outfoxed by tricksy agents using poison, reverse psychology, or even the 'Look! Behind you!' trick.
Example of speshul canon characters are Eragon, Drizzt do'Urden, and Neo.
Being speshul is a charge.