Aether.

[He repeats, then hums to himself thoughtfully.]

Hmmm... How best to explain?

Aether is energy. It is the source of magic and of life itself. Think of it as... your spiritual essence even if that is not entirely accurate.

Hah.

[Fandaniel throws his gloved hands up and shakes his head.]

I'm certain such a concept exists in other worlds, but I wouldn't know the name for it.