It was an in joke.

这是小圈子里的一个玩笑。

youdao

The headmaster at my school decided to play an April Fools' joke on the students when I was in high school.

在我上高中的时候，我们学校的校长决定给学生们开一个愚人节玩笑。

youdao

The OED defines LOL as an interjection "used chiefly in electronic communications… to draw attention to a joke or humorous statement, or to express amusement".

《牛津英语词典》将 LOL 定义为一个叹词，“主要用于电子通信……以引起对笑话和幽默语句的注意，或表示可笑”。

youdao

It reminds me of a joke about the statistician who drowned in a pool with an average height of 10 inches.

这让我想起一个统计学笑话,在一个平均水深为10英寸的游泳池里，谁会被淹死。

哈佛公开课 - 幸福课课程节选

Without the novelty of a CEO getting drowned out by his own product (with an in-joke to boot), this ad simply showed someone blowing off her real-world relatives for her more exciting friends doing more exciting things.

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There is an old joke in the world of business software that ERP is a roach motel where data goes to die.

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"There's an old joke in the South, " he explained.

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