Fluidic space

Fluidic space or (fluid space) is a fictional concept in the television series Star Trek: Voyager.

Fluid space is a different dimension (outside of our universe) inhabited by the advanced Species 8472. Fluid space is apparently a continuum filled with an organic fluid. In the episode Scorpion, Part II, the Borg discover Species 8472 in the Delta Quadrant and try to assimilate their bio-technology which is more advanced than anything the Borg have seen. The Borg open a rift in space using a deflector dish, trying to conquer fluidic space. However, Species 8472 is extremely resistant to the Borg's efforts to conquer them, and end up fighting and prevailing against the Borg in normal space. The crew of the U.S.S. Voyager help the Borg defeat Species 8472 and send them back into fluidic space. In return, the Borg allowed Voyager safe passage through their space for a limited time.