Kewl is the swedish word for describing something/someone funny.
Probably copied by random people who thinks it's pronounced '
cool' and then used it as if it meant '
cool'.
Later, people got annoyed of it and made themselves look like shitheads by defining it on
Urbandictionary.com. The same people later gave this defination a thumb down because they felt offensed by it.
And even later, this defination got deleted and no one could read it any longer. But by then, no one cared.