A shortend version of garunteed, used when something is really good. Can also be a replacement for any word, used because you feel like saying GARUNS!
Mostly used by chavs/townies/nutters/jesus
Man: Check this out... *Points at something really fantasmic* (see fantasmic)
Jesus: ah Garuns!
Example 2- (when you just feel like saying garuns)
Jesus: Oi you! Check out the size of my garuns!