Nervograp

noun
Specialised animal tissue bred to transmit signals over long distances.
Source
The Crucible of Time

Cloudhook

noun
A portable device worn over the eye by citizens, connecting them to the city’s pervasive information network.
Source
A Memory Called Empire

Cryptosphere

noun proper
A networked worldwide data repository, containing the sum of recorded knowledge and populated by uploaded human minds.
Origin
Crypta (vault), from kruptós (hidden).
Source
Feersum Endjinn

Metacortex

noun
A distributed cloud of software agents that augments the computational power of the human brain.
Source
Accelerando

Cyberspace

noun
A graphic representation of data abstracted from the banks of every computer in the human system.
Source
Neuromancer