Female Nazgûl???

[Morthoron]

Originally Posted by Rhun charioteer

While the Nazgul were all most certainly men. I don't see why hypothetically Sauron would have not given a ring to say a powerful easterling queen or sorceress under his control. No doubt in the east and south in middle earth there were such queens under his sway.

It would all depend. It couldn't be a plain ring. It would have to be a ring that could be accessorized, otherwise Sauron would be jilted.