flash in the pan

Cultural  

1. Someone or something that promises great success but soon fails: “The rock group that was all the rage last year turned out to be just another flash in the pan.”

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flash in the pan Idioms  

1. An effort or person that promises great success but fails. For example, His second novel proved to be a flash in the pan, or We had high hopes for the new director, but she was a flash in the pan. This metaphoric term alludes to the 17th-century flintlock musket, which could be fired only when the flash of the priming powder in the lockpan ignited the charge in the bore. When it failed to ignite, there was only a flash in the pan and the gun did not shoot.

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Example Sentences

That could be a signal to the committee that Marvell’s recent ascent isn’t just a flash in the pan.

From MarketWatch • Jun. 5, 2026

The difference north of the border is that Hearts insists it isn’t a flash in the pan.

From The Wall Street Journal • May 15, 2026

"But you also need to have the right team around you to make sure it's not a flash in the pan and you can grow it in a sustainable way."

From BBC • Sep. 26, 2025

You can watch it and go, "Oh, you're just going home and you're just breaking up with these people. It's just a flash in the pan of your life," but it's a big moment.

From Salon • Nov. 28, 2024

This was followed by a telegram from Mississippi to the anti-ratificationists in Delaware that this Senate vote was only "a flash in the pan" and would be reconsidered.

From The History of Woman Suffrage, Volume VI by Harper, Ida Husted