second thought

American  

Or second-thought

noun

1. Often second thoughts. reservation about a previous action, position, decision, judgment, or the like.

   He had second thoughts about his decision.

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idioms

1. on second thought, after reconsideration.

   On second thought, I don't think I'll go.

second thought British  

noun

1. (usually plural) a revised opinion or idea on a matter already considered

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Etymology

Origin of second thought

First recorded in 1625–35

Example Sentences

It is in these jargon-rich, usually quiet meetings where so many data centers are approved without second thought.

From Salon • Jun. 12, 2026

But for Fatima, a 36-year-old German housewife travelling with her family, "there was no second thought" about coming to Mecca, Islam's holiest city.

From Barron's • May 22, 2026

Cars, which we jump into every day without a second thought, are not as safe statistically.

From MarketWatch • Apr. 9, 2026

On second thought, maybe that calls for something more formal.

From The Wall Street Journal • Mar. 13, 2026

“On second thought, I think y’all should go say hi to our new neighbors! And sweep the front stoop while you’re at it.”

From "Pride" by Ibi Zoboi