What was the nickname of the 1929 Wall Street Crash day on October 24?

The 1929 Wall Street Crash day on October 24 was nicknamed Black Thursday.

Black Thursday marked the first major panic day of the late-October 1929 collapse. Heavy selling pushed stock prices down, and trading volume reached a then-record level. A group of leading Wall Street bankers later bought shares to support prices, temporarily calming the market and helping create the impression that the crisis had been contained.

That confidence did not last. Selling intensified on Black Monday, October 28, and Black Tuesday, October 29. The sequence is why accounts of the crash often mention several named days rather than one isolated event.

Black Thursday is sometimes confused with Black Tuesday because Black Tuesday became the more famous label. The earlier day, however, was October 24. The crash unfolded after years of rising share prices, widespread speculation, and purchases made with borrowed money, although the economic consequences developed over a longer period.