flapping

1. (phonology) A phonological process found in many dialects of English, especially American English and Canadian English, by which intervocalic /t/ and /d/ surface as the alveolar flap [ɾ] before an unstressed syllable, so that words such as "metal" and "medal" are pronounced similarly or identically.countableuncountable

2. (computing, telecommunications) The situation where a resource, a network destination, etc., is advertised as being available and then unavailable (or available by different routes) in rapid succession.countableuncountable

3. (uncountable) The unlicensed racing of horses or greyhounds.Examples: "Greyhound racing had its origins in whippet racing, which was derived in turn from hare coursing. By the early twentieth century, however, a form of dog racing held in 'flapping tracks' was a common pastime in the wastelands near working-class areas of industrial cities."; "Flapping is racing which is not licensed by the Jockey Club. […] Anyone found participating in, or even attending, flapping races is liable to be warned off."; "Flapping is the arse end of greyhound racing, the lowest of the low. Part sport, part fairground attraction, flapping is the bare-knuckle fighting of dog racing."uncountable