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

He told his parents he had noticed an identical one on the bar, picked it up and put it in his pocket without a second thought - not realising it belonged to somebody else.

From BBC • Apr. 24, 2026

The second thought explicit directions were a mere suggestion and not to be followed.

From The Wall Street Journal • Apr. 22, 2026

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

From MarketWatch • Apr. 9, 2026

He was like, ‘Nah, I don’t think acting is my passion, but I’ll never forget those moments … You know what? On second thought, it depends on the script.’

From Los Angeles Times • Feb. 23, 2026

I raised my hand once more without a second thought.

From "March Forward, Girl" by Melba Pattillo Beals