First, thank you for being the only person to offer a definition.
I am convinced that sound definitions are the crux of any discussion. Their lack is why so many discussions fail. They are the ultimate strength of science, mathematics, and good philosophy - all three fall apart the moment a loose or imprecise definition is included in part of an argument. Coversely, lack of sound definition is the bedrock of religion and superstition.
In what way does the supernatural have nothing to do with reality?
In the most fundemental way. It is a meaningless term precisely because it has never had any connection with reality. It has zero success in providing any form of consistent predictive power, and thus I can substitute gibberish for any given supernatural explanation and achieve equal success. This is in stark contrast to reality. I thus conclude that the supernatural is synonymous with that that is not real, that that does not exist.