Idiom idiom
under the illusion
Meaning
Having a mistaken belief about something.
Meaning adapted from Wiktionary, available under CC BY-SA 4.0.
Examples
“He is under the illusion that he can win.”
“She was under the illusion that the project would be easy, but it took much longer than expected.”
“The politician remained under the illusion that the public still supported his policies, despite the overwhelming evidence of his declining popularity.”
Anchors to
Last updated August 10, 2026