What term describes the rapid 6 May 2010 US market plunge and rebound?

The rapid US market plunge and rebound on 6 May 2010 is known as the Flash Crash.

On that afternoon, major US stock indexes fell extremely quickly before recovering much of the loss. The Dow Jones Industrial Average briefly dropped about 1,000 points, or roughly 9%, within minutes. Many individual securities also traded at unusually low prices before normal market conditions returned.

Investigations connected the event to a combination of high-frequency trading, automated selling, market fragmentation, and a large sell order. The US Securities and Exchange Commission and Commodity Futures Trading Commission concluded that automated systems amplified the initial pressure, although the episode involved several interacting factors.

The Flash Crash differed from a conventional bear market because its most dramatic movement unfolded within minutes and was followed by a rapid partial recovery. Afterward, US exchanges introduced or strengthened safeguards such as market-wide circuit breakers and limit-up-limit-down rules.