All 5 Uses of

labyrinth
in
Oryx and Crake

To access the more disgusting and forbidden sites — those for which you had to be over eighteen, and for which you needed a special password — Crake used his Uncle Pete's private code, via a complicated method he called a lily-pad labyrinth.†
p. 86.0

Still, they dutifully lit up a joint, hacked into Uncle Pete's digital charge card via a new labyrinth, and started surfing.†
p. 89.6 *

It could be dangerous — it could leave a footprint for anyone who might manage to trace a way through the labyrinth — but Crake did it anyway.†
p. 91.3

He was to cudgel his brains and spend ten-hour days wandering the labyrinths of the thesaurus and cranking out the verbiage.†
p. 248.3

Definitions:

(1) (labyrinth)
a maze (a complex system of paths or tunnels in which it is easy to get lost)

or (figuratively): anything so complicated that it is extremely confusing

The word "labyrinth" comes from the name of the maze of passages where, in Greek mythology, Theseus had to escape from the Minotaur.
(2) (meaning too rare to warrant focus)
meaning too rare to warrant focus:

Less commonly, labyrinth can refer to a complex anatomical system of interconnecting cavities -- especially the inner ear