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

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

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

Whether that will make Leverkusen perennial contenders or a one-season flash in the pan remains to be seen.

From Los Angeles Times • Apr. 16, 2024

“While inflation was hotter than it’s been in a while, it may be more of a flash in the pan than the start of something worse,” said Brian Jacobsen, chief economist at Annex Wealth Management.

From Seattle Times • Feb. 29, 2024

Salvationism may be only a flash in the pan; but, on the other hand, it may provide the only sort of Christianity possible in an age of science and freethought.

From Arrows of Freethought by Foote, G. W. (George William)