Deathly and hallows?

What's deathly about hallows? Deathly veneration? deathly saints? JK does not explain the meaning afraid that it'll give away a clue to the story....but as the countdown goes on cant think of much else these days....it's damn frustrating to be a muggle and be content with reading it with the rest of the world!

Awaiting eagerly...here's a toast to bringing magic into millions of lives!