sinkhole
noun
Definitions
A hole formed in soluble rock by the action of water, serving to conduct surface water to an underground passage
Synonyms:cenotedolinadolinekettle holeshakeholesinkswalletswallow holeA depressed area in which waste or drainage collects.
A hole in the playfield that rewards the player when the ball is guided into it.
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.