FALLACY Synonyms: 61 Similar and Opposite Words

fallacy

noun

ˈfa-lə-sē

Definition of fallacy

as in delusion

a false idea or belief the once-common fallacy that girls just weren't any good at math

Synonyms & Similar Words

Relevance

Antonyms & Near Antonyms

truth
verity

as in deception

the quality or state of being false the fallacy of the notion of spontaneous generation was demonstrated by the Dutch naturalist Leeuwenhoek

Synonyms & Similar Words

Antonyms & Near Antonyms

Example Sentences

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.

Recent Examples of fallacy The sunk cost fallacy is the silent killer of rational decision-making. — Daniel S. Levine, PEOPLE, 12 May 2026 Like being able to recognize logical fallacies and how to have media literacy. — Phillip Sitter, Des Moines Register, 7 May 2026 For example, the false dilemma logical fallacy has become a very popular way to persuade people to incorrectly believe there are only two options. — Kaitlyn Schallhorn, Oc Register, 4 May 2026 Since the city adopted the video release policy more than a decade ago, experience has repeatedly demonstrated the fallacy of limiting inquiry to the precise moment when a police officer fires their gun. — Jamie Kalven, Chicago Tribune, 29 Apr. 2026 See All Example Sentences for fallacy

Recent Examples of Synonyms for fallacy

Noun

But a line like that also fleshes out the head-in-the-stratosphere delusions of everyone here.

— Ryan Lattanzio, IndieWire, 8 Oct. 2026
The company has also been sued by the parents of kids who took their own lives, alleging that ChatGPT encouraged suicide and harmful delusions.

— James Peckham, PC Magazine, 5 Oct. 2026

Definition of delusion

Noun

Most often, this would be a network of fake accounts discovered by social media companies as part of their efforts to eliminate bots, scams, and online deception on their platforms.

— RENÉE DIRESTA, Foreign Affairs, 5 Oct. 2026
In writing her for the series, Kazan realized Cathy, despite her deceptions, is almost always telling the truth.

— Lexy Perez, HollywoodReporter, 4 Oct. 2026

Definition of deception

Noun

Of course, the retort is that this would be irritating and exasperating to be continually deluged with alerts about AI deceptiveness.

— Lance Eliot, Forbes.com, 24 Aug. 2025
Beyond the deceptiveness of the narrow material view, spiritual light and hope are always present to be found and felt.

— Sue Brightman, Christian Science Monitor, 3 Jan. 2025

Definition of deceptiveness

Noun

Another factor is the effect of radiation on the chips powering the data centers which can cause errors.

— Marco Quiroz-Gutierrez, Fortune, 10 Oct. 2026
That's out of nearly 190,000 reports made about the drug over that period, most of which included minor gastrointestinal issues, dosing errors or injection site redness.

— Yuki Noguchi, NPR, 10 Oct. 2026

Definition of error

Noun

Christy orchestrates the elaborate stagecraft that sells the illusion of a bustling organization.

— Robert Lloyd, Los Angeles Times, 8 Oct. 2026
When the team built a setup to directly quantify real-time heat flux alongside electrical output, the theoretical illusions collapsed.

— Mrigakshi Dixit, Interesting Engineering, 8 Oct. 2026

Definition of illusion

Noun

But at the prospect of engagement dropping by even one percent, Zuckerberg rules out any serious measures against content violation, making Charlie furious by refusing to consider policing political ads for falsehoods.

— David Rooney, HollywoodReporter, 7 Oct. 2026
Despite this online onslaught, many actors across sub-Saharan Africa are actively standing up to combat falsehoods with facts.

— the Monitor's Editorial Board, Christian Science Monitor, 6 Oct. 2026

Definition of falsehood

Browse Nearby Words

fallaciousness

fallacy

fal-lal

See all Nearby Words

Cite this Entry

Style

“Fallacy.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/fallacy. Accessed 11 Oct. 2026.

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Synonyms of fallacy

noun

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