Definition of "sinkhole"

sinkhole

noun
plural sinkholes
1. (geology) A hole formed in soluble rock by the action of water, serving to conduct surface water to an underground passage.
  Quotations
  A sinkhole suddenly opened up beneath the track of a heavy freight route in the eastern United States. Golfers playing the 13th hole at Hartford, Connecticut, had a new obstacle to tackle: a section of track suspended in mid-air after heavy rainfall in the aftermath of Storm Ida.
  2021 September 22, “Network News: Sinking feeling on unlucky 13th”, in RAIL, number 940, page 18
2. A depressed area in which waste or drainage collects.
3. (pinball) A hole in the playfield that rewards the player when the ball is guided into it.
  Quotations
  Pro Pinball is as authentic as pinball has ever been on the PC. It's all here, from the ramps, bumpers and sinkholes to the satisfying "clack" when you make the high-score list.
  1997, Windows magazine, volume 8, numbers 1-3
4. (Internet) A domain name server that has been configured to hand out non-routeable addresses for all domains, so that every computer that uses it will fail to get access to the real website.
5. (computer security) An attack which redirects requests - be it network or memory accesses - to a new location defined by the attacker.
verb
third-person singular simple present sinkholes, present participle sinkholing, simple past and past participle sinkholed
1. (Internet, transitive) To configure as a sinkhole (domain name server that gives non-routeable addresses).