on second thought
- 1After reconsidering a matter or giving it further thought, often leading to a changed decision.
On second thought, perhaps I shouldn't have sent that email so quickly.
She agreed to lead the project, but on second thought asked for a few more days to decide.
Note
An American turn of phrase for changing your mind mid-sentence. It usually sits at the front of its clause and signals a reversal, as in "it was a good idea, but on second thought I'm not so sure." The singular thought is the US form, while British speakers tend to say on second thoughts. Then again is a looser neighbor: it adds a counterpoint without necessarily withdrawing anything.
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