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Synonyms

fixed idea

American  

noun

  1. a persistent or obsessing idea, often delusional, that can, in extreme form, be a symptom of psychosis.

fixed idea British  

noun

  1. Also: idée fixe.  an idea, esp one of an obsessional nature, that is persistently maintained and not subject to change

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of fixed idea

First recorded in 1820–30

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Vallejo also dedicated three summers to the caddie program, getting up early, enduring the heat and carrying heavy bags, always with a fixed idea in mind.

From Los Angeles Times • May 28, 2025

Getting a new view on someone I had such a fixed idea of who or want he was, and this is a way of understanding that.

From Salon • Jul. 6, 2023

“There was a fixed idea that politics is for adults, according to a long-established Confucian culture,” said Noh Woong-rae, 64, a member of the National Assembly.

From New York Times • Jul. 4, 2022

I was interested in having an audience that has a fixed idea of these women’s racial identity.

From Washington Post • Nov. 13, 2021

R. M. Renfield, ætat 59.—Sanguine temperament; great physical strength; morbidly excitable; periods of gloom, ending in some fixed idea which I cannot make out.

From "Dracula" by Bram Stoker

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.