What was the name of the 1929 crash-era economic catastrophe that followed the market collapse?

The economic catastrophe associated with the 1929 crash was the Great Depression.

The Great Depression was a worldwide economic crisis that began in 1929 and lasted through much of the 1930s. The Wall Street Crash severely damaged American wealth and confidence, but the depression resulted from a wider combination of forces, including banking failures, collapsing prices, reduced production, falling international trade, and restrictive monetary conditions.

The crisis was especially severe in the United States, where unemployment rose dramatically and industrial output contracted. Its effects also spread internationally through trade, lending, and the gold standard. Different countries experienced different timing and severity, and recovery policies varied.

A common mistake is to say that the stock-market crash by itself instantly caused the entire depression. The market collapse was an important early shock, but the prolonged economic disaster developed through interacting financial and policy problems. The Great Depression also differs from the Great Recession, the name commonly used for the global crisis beginning in 2007–08.