The hockey world is still buzzing over Erik Karlsson's horrific injury, with the debate raging on about whether the awkward hit by Pittsburgh’s Matt Cooke should be considered dirty.

Well, maybe “debate” isn’t the right word; outside of Ottawa, the play is mostly seen an unfortunate accident. But “raging” probably still fits, at least when it comes to minority opinions like this tirade from Senators owner Eugene Melnyk.

But the bigger problem here is that we often don’t even know what “dirty” means. The term can describe different things to different fans, and these days it casts a wide enough net that it is often meaningless.

We need more than just “dirty” or “not dirty." So I’ve taken a crack at breaking down the seven levels of dirty. I’ve also included some examples — a list that, unfortunately for hockey fans, is far from definitive — a well as the short- and long-term consequences. It won’t settle all the arguments, of course, but at least it might help us figure out what we’re arguing about.