1
as in delusion
a false idea or belief
the once-common fallacy that girls just weren't any good at math
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Antonyms & Near Antonyms
2
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
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Antonyms & Near Antonyms
Example Sentences
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Recent Examples of fallacy
This mindset, however, can also foster a sunk cost fallacy.
—
Kumar Rakesh Ranjan,
The Conversation,
27 Apr. 2026
The fallacy of first is demonstrated by the Netscape, Napster, Sony’s Betamax, GM’s EV1 electric vehicle, Kodak’s first digital camera in 1975, and UPS’ launch of an overnight delivery service in 1929 as potent reminders that being first is not the winning formula; being the best is.
—
Jeffrey Sonnenfeld,
Fortune,
21 Apr. 2026
This was the fallacy that led to the rise of elegant, beautiful, and compelling scenarios — grand unification, supersymmetry, extra dimensions, and string theory — whose predictions simply don’t appear to match experimental reality in any measurable way.
—
Big Think,
1 Apr. 2026
Rose pointed out that our decision-making, especially System 1 decision-making, is affected by cognitive biases and logical fallacies.
—
Neil J. Rubenking,
PC Magazine,
26 Mar. 2026
See All Example Sentences for fallacy
Kumar Rakesh Ranjan,
The Conversation,
27 Apr. 2026
The fallacy of first is demonstrated by the Netscape, Napster, Sony’s Betamax, GM’s EV1 electric vehicle, Kodak’s first digital camera in 1975, and UPS’ launch of an overnight delivery service in 1929 as potent reminders that being first is not the winning formula; being the best is.
—
Jeffrey Sonnenfeld,
Fortune,
21 Apr. 2026
This was the fallacy that led to the rise of elegant, beautiful, and compelling scenarios — grand unification, supersymmetry, extra dimensions, and string theory — whose predictions simply don’t appear to match experimental reality in any measurable way.
—
Big Think,
1 Apr. 2026
Rose pointed out that our decision-making, especially System 1 decision-making, is affected by cognitive biases and logical fallacies.
—
Neil J. Rubenking,
PC Magazine,
26 Mar. 2026
See All Example Sentences for fallacy
Recent Examples of Synonyms for fallacy
Noun
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By chance, Rhaena arrives at the Gullet on dragonback just in time to make the same hubristic mistake as her sister and her cousin, all suffering from the delusion that the war needs them.
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Schizoaffective disorder is a mental health condition that is marked by a mix of schizophrenia symptoms, such as hallucinations and delusions, and mood disorder symptoms, such as depression, mania and a milder form of mania called hypomania, according to the Mayo Clinic.
Noun
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So, that's a kind of deception.
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The county argues the grand jury fundamentally misunderstood what happened before the explosion, saying its investigation relied on speculation instead of evidence and wrongly blamed county officials for a criminal enterprise prosecutors say was built on years of deception.
Noun
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The piece’s name is also a nod to a Greek myth, in which the 50 daughters of King Danaos—the Danaïdes—were ordered to kill their husbands on their wedding night.
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Reinventing the Batman myth for a new generation of fans, Absolute Batman reimagines the Dark Knight as a working-class hero up against impossible odds on a mission to prove that even in an era of wealth, power and corruption, one good person can change the world.
Noun
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Of course, the retort is that this would be irritating and exasperating to be continually deluged with alerts about AI deceptiveness.
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Beyond the deceptiveness of the narrow material view, spiritual light and hope are always present to be found and felt.
Noun
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With Yerry De los Santos also fumbling a bunt in the eighth, the Yanks tallied a season-high four errors on the night.
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Michael Conforto, Alex Bregman and Ian Happ had RBI hits in the sixth, when the Cubs’ runs were unearned thanks to a pair of errors.
Noun
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The falseness of the medium, though, jibed with the falseness of most attempts, throughout American history, to make sense of this enormous, strange man.
Noun
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Cosm has really cut its teeth on a lot of live sports and concert films, with the dome shape and stadium seating designed to give the illusion of being on the field or in the front row.
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Unfortunately, says Bradley Elliott, a researcher at the University of Westminster and trustee for the British Society for Research on Ageing, this is an illusion.
Noun
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This matters because cancer falsehoods online are directly linked to higher rates of death, studies have found.
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Diplomats are paid to lie for their country, but this may be the greatest and most obvious falsehood ever uttered by a diplomat not named Sergey Lavrov.
Cite this Entry
“Fallacy.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/fallacy. Accessed 26 Jun. 2026.
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