There’s nothing like striking Wikipedia gold. Megastructures:
A topopolis is a tube-like space habitat, rotating to produce gravity on the inner surface, which is extended into a loop around local star. Topopoli can be looped several times around the local star, in a geometric figure known as a torus knot.
The variant of the Dyson sphere most often depicted in fiction is the “Dyson shell”: a uniform solid shell of matter around the star. Such a structure would completely conceal the emissions of the central star, and would intercept 100% of the star’s energy output. Such a structure would also provide an immense surface which many envision being used for habitation, if the surface could be made habitable.