I'm being super pedantic here, but see how you said hybrid before solid state in your third sentence when explaining it? That's basically what I just suggested would be a clearer name.
Hybrid disk would be the generic term.
There has been work on liquid-state storage.
So Solid State becomes the adjective modifier for providing the classification of the type of Hybrid Disk.
You could in theory have a Liquid State Hybrid Disk, or a Liquid Solid State Hybrid Drive.