black holenoun Astronomya region of space having a gravitational field so intense that no matter or radiation can escape.Black holes are probably formed when a massive star exhausts its nuclear fuel and collapses under its own gravity. If the star is massive enough, no known force can counteract the increasing gravity, and it will collapse to a point of infinite density. Before this stage is reached, within a certain radius (the event horizon), light itself becomes trapped and the object becomes invisible.• informal a figurative place of emptiness or aloneness : they think he's sitting in a black hole with no interaction with his people.• informal chiefly humorous a place where money, lost items, etc., are supposed to go, never to be seen again : the moribund economy has been a black hole for federal funds | I wouldn't dare go in that black hole he calls a “garage.”• informal (of a system, practice, or institution) a state of inadequacy orexcessive bureaucracy in which hopes, progress, etc., become futile :juveniles lost for good in the black hole of the criminal justice system.