A black hole is a collapsed star whose pull is so strong that not even light escapes. Nothing that crosses the edge comes back.
That edge is the event horizon, and it is a boundary rather than a surface. They form when a massive star collapses, and there is one at the centre of nearly every galaxy including ours. The first photograph of one was published in 2019. The figurative sense is very common, since a black hole in a budget is money that has vanished with nothing to show.
1phraseblack holeA region of space with gravity so strong that light cannot escape.
“The galaxy has a supermassive black hole at its centre.”
2phrasemoneySomething into which money or effort disappears without result.
“The project became a black hole for public money.”
In reference to the physical concept (region of spacetime with extreme gravitational pull), physicist Hong-Yee Chiu attributed the term to his colleague coined by Robert H. Dicke, who stated around 1960–1961 that the objects were like the Black Hole of Calcutta. The first known usage in print was by journalist Ann Ewing in 1964. Widespread popularization of the term is generally credited to a lecture in 1967 by the physicist John Wheeler.
Etymology from Wiktionary, CC BY-SA
Practised in Science & Space, A Man Called Ove
First appears in chapter 29 of A Man Called Ove.
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