• 1A region of space having a gravitational field so intense that no matter or radiation can escape.

  〔天文〕黑洞

  Example sentencesExamples

  • I can only assume, based on our limited understanding of space and time, that the intense gravity of the black hole caused the spacecraft to be thrust back in time.
  • The gravitational field of a black hole is so strong that the escape velocity needed is greater than the speed of light.
  • This universe is very similar to our own, with thousands of stars and galaxies, black holes, comets and meteors each a part in the never-ending celestial dance.
  • An astronomy satellite that studied black holes and distant galaxies was wiped out by the one star that it did not watch.
  • Some of the invisible dark matter that is missing from the Universe may be massive dark bodies such as planets, black holes, asteroids or failed stars.

  1. 1.1informal A place where money or lost items apparently disappear without trace.
     Example sentencesExamples

     • The single biggest problem with the privatisation programme is that the proceeds disappear into a black hole called the Consolidated Fund of India.
     • But if you can't sell it, then you haven't got any money, what you've got is a big black hole of expense.
     • There is plenty of potential - the telecom's £2.5bn black hole alone is the equivalent to the value of a large UK company.
     • They disappear into the black hole existing somewhere in the core of my house.
     • Due to the ephemeral nature of the medium, web content often disappears into a black hole.
     • The economics of nuclear energy are insane - it's the most expensive way of generating electricity, a gigantic black hole sucking in taxpayers' money.
     • Publicly owned cars are a very big financial black hole in the country, producing waste and corruption.
     • Some sites we have looked at during the last few years have disappeared into the black hole of Cyberspace.
     • How many times have you sent an e-mail to a company, only to have that e-mail apparently fall into a black hole?
     • Are these savvy businessfolk simply throwing their money into a black hole?
     • But the critics assume that Quebecers get nothing in exchange for their tax dollars, that this money is somehow dumped into a great bureaucratic black hole.
     • Apparently he would like them to disappear into a black hole somewhere.
     • But in today's changing world, where today's Internet success can easily become tomorrow's black hole, it pays to have partners and spread the risk.
     • The company's finances are formally a black hole, although great hopes rest on the imminent IPO reviving the tech sector.
     • It's like a big black hole, the money disappears.
     • Dotcoms continue to disappear into the Nasdaq black hole in hot pursuit of the latest startups.
     • He adopted all these ruinous procedures and a very large percentage of what he thus raised went straight into his financial black hole.
     • Critics predicted that, without radical change to make the service more accountable, the money would disappear into a black hole.
     • The first disappeared into the great black hole of cyberspace.
     • They claim that all this extra cash has somehow disappeared into a black hole so massive that even Stephen Hawking could not comprehend it.

     Synonyms

     underground cell, underground prison, oubliette

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