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

The Mayo Clinic defines the mental health condition as typically marked by hallucinations, delusions, depression, and mania.

— Leigh Blickley, Entertainment Weekly, 29 Sep. 2026
Hill became increasingly paranoid and developed delusions that she was being surveilled.

— Rebecca White, New York Daily News, 28 Sep. 2026

Definition of delusion

Noun

Magpies are opportunistic scavengers, incredibly cunning and deceitful and capable of calculated deception.

— Voice of the People, New York Daily News, 28 Sep. 2026
This experience combines identity deception, autonomous agent action and software supply-chain risk, along with social engineering devised by an agent and directed against a human.

— Carlo Tortora Brayda, Forbes.com, 28 Sep. 2026

Definition of deception

Noun

After decades of perspective-shifting literary retellings like Wide Sargasso Sea and The Mists of Avalon and the current trend of feminist Greek myths, Cathy is an enigma begging for some traumatic backstory to staple her flaws together.

— Kathryn VanArendonk, Vulture, 1 Oct. 2026
Some myths about private capital persist for small-business owners, especially around what an investment actually means for a company.

— Frank Williamson, Forbes.com, 1 Oct. 2026

Definition of myth

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

On Friday, the Rams waived punt returner Xavier Smith, who fumbled in last season’s NFC championship game and made several decision-making errors against the Broncos.

— Gary Klein, Los Angeles Times, 3 Oct. 2026
Days later, campus administration clarified that their initial communication was an error.

— Tarini Mehta, Sacbee.com, 2 Oct. 2026

Definition of error

Noun

But recent Ukrainian drone strikes on Russia’s oil refineries have led to widespread fuel shortages, shattering the illusion that the consequences of the conflict are far removed from ordinary Russians.

— Zahra Ullah, CNN Money, 1 Oct. 2026
Use your illusion Hancock and his team combined multiple lines of evidence to test their hypothesis that the colorful wing patterns of butterflies served as a form of motion dazzle.

— Jennifer Ouellette, ArsTechnica, 30 Sep. 2026

Definition of illusion

Noun

The second, given by Stille, enlisted a recurrent theme in Eco’s fiction — how falsehood often trumps truth — to discuss the crisis of liberal democracy and its institutions.

— Bartolomeo Sala, The Dial, 29 Sep. 2026
Lindsay helpfully published a list of ten resources for debunking the most persistent falsehoods related to the attacks.

— Brian Stelter, CNN Money, 10 Sep. 2026

Definition of falsehood

Browse Nearby Words

fallaciousness

fallacy

fal-lal

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“Fallacy.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/fallacy. Accessed 5 Oct. 2026.

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Synonyms of fallacy

noun

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