Definition of FALLACY (original) (raw)
1
a
: a false or mistaken idea
prone to perpetrate the fallacy of equating threat with capability—
C. S. Gray
b
: erroneous character : erroneousness
The fallacy of their ideas about medicine soon became apparent.
3
: an often plausible argument using false or invalid inference
Did you know?
Philosophers are constantly using the word fallacy. For them, a fallacy is reasoning that comes to a conclusion without the evidence to support it. This may have to do with pure logic, with the assumptions that the argument is based on, or with the way words are used, especially if they don't keep exactly the same meaning throughout the argument. There are many classic fallacies that occur again and again through the centuries and everywhere in the world. You may have heard of such fallacies as the "ad hominem" fallacy, the "question-begging" fallacy, the "straw man" fallacy, the "slippery slope" fallacy, the "gambler's" fallacy, or the "red herring" fallacy. Look them up and see if you've ever been guilty of any of them.
Synonyms
Examples of fallacy in a Sentence
The fallacy of their ideas about medicine soon became apparent. the once-common fallacy that girls just weren't any good at math
Recent Examples on the Web
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.
Landman, set in the oil fields of West Texas, is punctuated by extensive diatribes from Tommy about the oil industry’s importance, the tragic necessity of landmen and roughnecks, and the fallacy of placing society’s hope on renewable energy. —Nicholas Quah, Vulture, 20 Dec. 2024 The argument that somehow voters in more populous states are disenfranchised is also a fallacy. —Joe Battenfeld, Boston Herald, 19 Dec. 2024 Already a #1 Sunday Times bestseller and has been shortlisted for the Nero Book Awards, An African History of Africa corrects many of the misguided fallacies that pervade Western narratives about Africa. —Lynnette Nicholas, Essence, 18 Dec. 2024 The report focuses on the fallacies in these arguments. —Marybeth Gasman, Forbes, 15 Dec. 2024 See all Example Sentences for fallacy 
Word History
Etymology
Latin fallacia, from fallac-, fallax deceitful, from fallere to deceive
First Known Use
15th century, in the meaning defined at sense 2b
Time Traveler
The first known use of fallacy was in the 15th century
Dictionary Entries Near fallacy
Cite this Entry
“Fallacy.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fallacy. Accessed 31 Dec. 2024.
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Last Updated: 30 Dec 2024 - Updated example sentences
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