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

But some children were also under the impression that there had been significant organised fighting or even that people had been killed, for which there's no evidence at all.

From BBC

Major Puff was still under the impression that Handsome was a great black-backed gull, which Handsome definitely was not.

From Literature

In their research, Meyer and Council found that 5200 is not known to be in use in any of the state’s 58 counties, with public officials either unaware of it or under the impression that it’s an unnecessary tool given other initiatives over the decades, and cost of implementation could be a problem.

From Los Angeles Times

An inattentive mortician, under the impression that a different corpse is William, inadvertently provides a body; mentioning insurance, he plants an idea in Debbie’s mind — that it might be profitable, which is not say practical, to leave William deceased in the eyes of the world.

From Los Angeles Times

Some cycling advocates say they were under the impression additional vouchers — that would have been funded by the subsequent $18 million in state funding — were on the horizon as soon as a new administrator of the program was secured.

From Los Angeles Times