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

I was under the impression that a logical qubit had perfect fidelity.

From Barron's • May 21, 2026

The couple said they were under the impression they were being compensated to be actors in a movie.

From Los Angeles Times • Dec. 31, 2025

The Miami crowd, under the impression they were there to be entertained, hissed and booed.

From The Wall Street Journal • Dec. 20, 2025

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

My advice will often shock purists and occasionally puzzle readers who have always been under the impression that this word meaning or that grammatical usage is an error.

From "The Sense of Style" by Steven Pinker