Necrosphere

noun
An airborne swarm of self-organising inanimate matter.
Origin
Nekrós (“the dead”).
Source
The Invincible

Rollstar

noun
Interior stars of a Shellword which roll across the upper surface of each layer.
Source
Matter

Archlight

noun
As seen from the inner surface, the reflected light from the skyward face of a ringworld.
Origin
So named because the skyward face resembles an arch overhead.
Source
Ringworld

Nestworld

noun
A type of artificial habitat composed of multiple twisting tubes, complexly intertwined.
Source
Matter

Shellworld

noun
An artificial planet comprising a solid core surrounded by a concentric succession of spherical shells.
Source
Matter

Spinward

adverb
In the direction of spin (of a rotating ringworld or orbital habitat.)
Source
Ringworld

Girdlecity

noun proper
A city that encircles a planet.
Source
The Hydrogen Sonata

Ringworld

noun
A ring-shaped artificial habitat encircling a star.
Source
Ringworld