The Nephilim and Nephilia

The "Sons of God" spoken of in the Hebrew scriptures are very definitely angels who were persuaded that human women were desirable. The offspring of these unions were indeed the Nephilim, half human, half demonic spirit creatures. No wonder the earth was filled with violence.

What fascinates me at the moment is that the constellation of Orion was called Nephilia by some ancient peoples. I am curious as to what the connection between Nephilia and Nephilim is? It would seem obvious, but it does not add up completely.