Definition of FALLACIOUS (original) (raw)
2
: tending to deceive or mislead : delusive
false and fallacious hopes—
Conyers Middleton
Did you know?
It will come as no surprise that fallacious is related to the noun fallacy, meaning “delusion” or “falsehood.” Both words come from the Latin word fallacia, which in turn comes from fallere, meaning “to deceive.” (Other descendants of fallere in English include fail, false, and fault.) Fallacious arguments are a hot topic among philosophers, and some classic examples include the “ad hominem” fallacy, the “slippery slope” fallacy, and the “red herring” fallacy.
Synonyms
Examples of fallacious in a Sentence
it's fallacious to say that something must exist because science hasn't proven its nonexistence consumers who harbor the fallacious belief that credit-card spending will never catch up with them
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.
That will in turn spread on social media, which often plays a disproportional role in boosting these disinformation efforts by providing nearly unlimited platforms for unfiltered content and fallacious and deceptive claims. —Peter Suciu, Forbes, 23 Dec. 2024 But hard evidence in both our nation’s history and our present shows that this reasoning is fallacious. —Ana Raquel Minian, TIME, 30 May 2024 And why not seek the truth, to give order and organization to a chaotic and fallacious narrative and investigative material? —Boris Sollazzo, The Hollywood Reporter, 28 Feb. 2024 This is such a fallacious argument and its presentation as acceptable is abhorrent to our standards of morality. —Letters To The Editor, The Mercury News, 24 Jan. 2024 See all Example Sentences for fallacious 
Word History
First Known Use
15th century, in the meaning defined at sense 1
Time Traveler
The first known use of fallacious was in the 15th century
Dictionary Entries Near fallacious
Cite this Entry
“Fallacious.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fallacious. Accessed 12 Feb. 2025.
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Last Updated: 29 Dec 2024 - Updated example sentences
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