This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

• Lexulous
• Wordscraper
• Wordosaur

n. A subset of a space which is a space in its own right.

n. Any (often unspecified) method of communicating faster than light.

n. The psychological state of the submissive or "bottom" during sadomasochistic activity.

n. a space that is contained within another space

"In fact, one might call subspace another dimension—which leads us to an interesting question."

topological space    mathematical space   

electro-magnetic    microwave    infrared    short-range    gravitational    sonic    electrical    radar    high-frequency    thermal