from The American Heritage® Dictionary of the English Language, 4th Edition
- n. Matter that emits little or no detectable radiation of its own, postulated to account for gravitational forces observed on astronomical objects and to be part of the missing mass.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. Particles of matter that cannot be detected by their radiation but whose presence is inferred from gravitational effects.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. (cosmology) a hypothetical form of matter that is believed to make up 90 percent of the universe; it is invisible (does not absorb or emit light) and does not collide with atomic particles but exerts gravitational force
Sorry, no etymologies found.