Quote Originally Posted by Ides Usher View Post
Scattered throughout the spheres that I have created are a number of worlds that are just not there. Moons orbit an empty area, a void.
Okay, so. One issue that I'm seeing is that you're trying to apply the word "world" to a distinct lack of world. Like, where one would expect a world to be, there is no world, if I'm understanding you correctly. There is no world to be described by any adjective, whether "void" or otherwise, but rather a void of a world. That's not a void world; that's a world void. Which I say partly as a potential name suggestion but mostly just, like, technically.

The general word for what a satellite orbits seems to be "primary", so maybe you could work that in. But it's worth noting that orbits around empty points are totally a real thing! The barycenter of two roughly equally massive objects tends to be a point between them rather than inside of either one, so they'll both go around that.

I don't know how well that fits how gravity works in Spelljammer, but I am somewhat amused by the idea of D&D spacefarers hypothesizing the existence of an intangible, undetectable object at a system's barycenter because they don't understand physics.