What term names the sudden U.S. equity-market plunge on May 6, 2010 that lasted about 36 minutes?

The sudden U.S. equity-market plunge on May 6, 2010, that lasted about 36 minutes is called the Flash Crash of 2010.

That afternoon, major U.S. indexes and individual securities dropped rapidly before recovering much of the loss. The Dow Jones Industrial Average briefly fell nearly 1,000 points, then rebounded. Investigations found that automated trading, fragile liquidity and a large sell order interacted in unusual ways.

The U.S. Securities and Exchange Commission and Commodity Futures Trading Commission later described a sequence involving algorithmic trading and market fragmentation rather than a single simple cause. New safeguards followed, including circuit breakers and clearer handling of erroneous trades. The event differs from a conventional multi-month bear market because its defining feature was extreme speed.