fallacious

adjective

fal·​la·​cious fə-ˈlā-shəs How to pronounce fallacious (audio)
1
: embodying a fallacy
a fallacious conclusion
a fallacious argument
2
: tending to deceive or mislead : delusive
false and fallacious hopesConyers Middleton
fallaciously adverb
fallaciousness noun

Did you know?

Oh what a tangled web we weave / When first we practise to deceive! So wrote Sir Walter Scott in his 1808 poem Marmion. Scott’s line wasn't written with etymology in mind, but it might be applied to the history of "fallacious." That word traces back to the Latin verb fallere ("to deceive"), but it passed through a tangle of Latin and French forms before it eventually made its way into English in the early 1500s. Other descendants of "fallere" in English include "fail," "false," and "fault."

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 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 Catherine Weller, director of global policy for Fauna & Flora International, tells Popular Mechanics that Barron’s argument is fallacious. Susan Lahey, Popular Mechanics, 24 July 2023 Bad legislation and fallacious arguments are threatening our most renowned educational institutions, which have made major contributions to our understanding of science and society and to our health and economic well-being, institutions that are the envy of the world. Burton G. Malkiel, WSJ, 19 Oct. 2022 But he's been criticized by some Republicans, mostly quietly, for relentlessly supporting Trump's fallacious claims of a fraudulent election last November and for not forcefully criticizing Trump for helping provoke the deadly Jan. 6 attack on the Capitol by his supporters. Alan Fram, BostonGlobe.com, 3 Feb. 2021 Jurors got the the analytics reports, mixed with Jones’ wildly fallacious broadcast denials of the shootings, during the third day of trial in a suit against Jones and his business by a first responder and relatives of the 26 students and educators who died. Edmund H. Mahony, Hartford Courant, 15 Sep. 2022 In practical terms, the statement was fallacious. Pedro Rios, San Diego Union-Tribune, 10 June 2022 This is fallacious for the same reason. Philip Goff, Scientific American, 10 Jan. 2021

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'fallacious.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

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

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Dictionary Entries Near fallacious

Cite this Entry

“Fallacious.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fallacious. Accessed 20 Apr. 2024.

Kids Definition

fallacious

adjective
fal·​la·​cious fə-ˈlā-shəs How to pronounce fallacious (audio)
1
: containing a fallacy
a fallacious argument
2
: leading in a wrong direction or into a mistaken action or belief
fallaciously adverb
fallaciousness noun

More from Merriam-Webster on fallacious

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