I’m watching Blender Today # 61, Colored Icons and see them talking about the name of the “balls” (now called spheres), that display the lighting for the world/hdr.
My suggestion is to called them Shading Orbs.
Orb is the important part, call them Look Dev Orbs, Dhader Orbs, Viewport Orbs, HDR Orbs, whatever, just use Orb instead of Sphere.
Sphere isn’t “incorrect” but I believe an orb would be better for this particular item.