Definition:Hyperspace/Also defined as

Definition

The word hyperspace is often used in the context of science fiction to mean a space-time continuum of $4$ dimensions in which time travel is possible.

Also see

• Results about hyperspaces can be found here.

Sources

• 1989: Ephraim J. Borowski and Jonathan M. Borwein: Dictionary of Mathematics ... (previous) ... (next): hyperspace: 2.