(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
(cosmoloxía) forma hipotética da materia que se cre que compón o 90% do universo; é invisible (non absorbe, nin emite luz) e non choca coas partículas atómicas, pero exerce forza gravitacional