under the impression

Idioms  

1. Thinking, assuming, or believing something, as in I was under the impression that they were coming today. This idiom often suggests that the idea or belief one had is mistaken. [Mid-1800s]

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Example Sentences

If you haven’t yet watched the limited series, you may be under the impression that this is a spoiler.

From Salon • Nov. 19, 2025

His mother was under the impression that he would do the fellowship as a gap year, and then reapply to return to college.

From The Wall Street Journal • Nov. 2, 2025

In fairness, I had also been under the impression that laws were laws.

From Slate • Oct. 17, 2025

Her family was under the impression she was studying dressmaking and following in the steps of her family.

From Los Angeles Times • Sep. 3, 2025

“I was under the impression that I was speaking to Mr. Gaunt,” said Ogden, looking wary, but standing his ground.

From "Harry Potter and the Half-Blood Prince" by J.K. Rowling