Infrastructure

Aksijaha - the root of the Eye; the central node of the Wormhole Nexus, (perhaps mythical)

Angelnet - Transapientech all-pervasive utility fog based distributed processing supervision and safety infrastructure found in many developed worlds, megastructures, and polities throughout terragen space, serving as a ubiquitous technological presence for protecting a sapient population or local subsystems, by eliminating both accidents and deliberate attacks.

Banks Orbitals - megastructure habitats shaped as a rotating open ring with a radius of more than a million kilometres; they are comparable to Bishop rings but require exotic atoms for their construction due to the stresses involved.

The Beamrider Network - the linked cycler routes that connect even those systems that are not a part of the Nexus

Bishop Rings - rotating open ring habitats constructed with carbon buckytube, often a thousand kilometers in radius

Brain Taxonomy - the various different kinds of intelligent megastructure, including Moonbrains, Jupiter-Brains, Neuron Stars, S-Brains, W-Brains, and Tipler Oracles

Dyson Sphere - a huge spherical megastructure or habitat swarm constructed around a star in order to maximise living space and capture the entire energy output of that star.

Dyson Trees - Genetically engineered trees employing bio-nanotech. Widely used as a biological space habitats

Canopy Plant - Canopy Plants are neogen plants used in terraforming, paraterraforming, or habitat creation

Space Canopy and Greenbubbles - A space-adapted variant of the Canopy Plant

Eders (also variously known as Ederbubbles, Edercolonies, Ederspheres, Ederhabitats, or Bubbleworlds.)

FullAirs - airborne arcologies supported by warm air

Habitats - living space for trillions of sapient beings

The Known Net - the interstellar information network and interlinked cybercosms that has grown over thousands of years from the old pre-singularity Internet and InterPlanetNet

Matrioshka Brain

Matrioshka Hypernode

McKendree Cylinders - closed cylindrical habitats, often a thousand kilometers in radius and ten thousand kilometers long

Niven Clouds -aka Smoke Rings  -   circumstellar freefall environments

Road Root - self-repairing biotech road and highway systems

Reef, Reefcity - cities built from coral-like bioengineered organisms

Supramundane Worlds Within the Terragen Sphere supramundane planets (also known as supra-planetary habitats and/or shells) can trace their origins back to the Supra-Jupiter concept of the information age visionary Paul Birch. Although others may also have had the idea it was Birch's work that survived the nanoswarms. Because of his early advocacy of Mass Stream Technology he is well written of in even current engineering texts.

Sunclouds - diffuse lighting systems for rotating habitats

Symmes' Worlds - A Symmes' World starts out as the shell of a supramundane planet. When the shell becomes thick enough it generates enough of a gravity well to hold on to a biosphere. Large openings in the shell (most often at the poles) called "Symmes' holes" allow the atmospheres, hydrospheres and biospheres of the outside surface and inside volume to mix

Valhalla Cluster -Colloquial term for massive artificial concentrations of matter believed to be operating as archai level (Fifth Singularity or higher) industrial centers.

Worldhouses - Also known as paraterraforming or pseudoterraforming, this technique is widely used by colonisation projects to produce suitable living conditions for baseline or nearbaseline humans relatively rapidly.

The Wormhole Nexus - the network of artificial wormholes that connects the galactic community

W-Brains - a form of distributed comptutational megastructure relying on wormholes for processing power

Yggdrasil Bush - a variant of the Dyson Tree which produces a canopy containing a breathable atmosphere