It refers to the Wall Street Crash of 1929, also known as the Great Crash, and the Stock Market Crash of 1929. iIt was the most devastating stock market crash in the history of the United States.

黑色星期二指1929年华尔街股灾，又称大股灾及1929年华尔街股市崩盘，是美国历史上最严重的一次股灾。

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A little over a decade ago, Nobel Prize-winning economist Edward Prescott did a study of stock prices in 1929, before that year's giant stock market crash.

十年多前，诺贝尔奖经济学奖得主爱德华·普雷斯科特在当年股市大崩盘前对1929年的股价进行了研究。

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The group calls itself Black Thursday, in memory of the 1929 stock market crash in the United States.

VOA: standard.2009.11.12

For example, the stock market crash of 1929 is repeatedly re-expected even though it only happened once; it's just prominent in our thinking.

929年股市崩盘,就被反复提及,尽管这只发生过一次,但是人们对它影响深刻

耶鲁公开课 - 金融市场课程节选

The stock market crash in 1929 caused tremendous chaos in the financial markets.

929年股票市场的坠落引起了金融市场,巨大的混乱。

耶鲁公开课 - 金融市场课程节选

The commission set out to discover what had led to the stock market crash in 1929.

CNN: Commentary: Investigate Wall Street

It raised fears about this being a repeat of the stock market crash of 1929 and a harbinger of an economic depression to follow.

BBC: The stock market crash of 1987: What have we learned?

The stock market crash of 1929 did not cause the Depression.

FORBES: Fact and Comment