noun
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the tendency to be untruthful
-
a falsehood
Other Word Forms
Derived Forms
Inflected Forms
Nouns
Etymology
Origin of mendacity
1640–50; < Late Latin mendācitās falsehood, equivalent to Latin mendāci- (stem of mendāx ) given to lying, false + -tās -ty 2
Explanation
Mendacity is a tendency to lie. Your friend might swear that he didn't eat your secret chocolate stash, but you'll find it hard to believe him if he's known for his mendacity. Anyone in the habit of lying frequently has the characteristic of mendacity. People often accuse government officials of mendacity, or being less than honest. You're bound to get frustrated by the mendacity of your friend who's a pathological liar. Mendacity comes from the Latin root word mendacium, or "lie." Don't confuse mendacity with a similar-sounding word, audacity — which means "fearlessness, daring, or bravery."
Vocabulary lists containing mendacity
A Web of Lies
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Pygmalion
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Word Warriors: Four Years of Words Worth Reviving
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
A few chapters occupy his immediate point of view, but the novel never tries to explain his mendacity and lack of feeling.
From The Wall Street Journal • Mar. 26, 2026
In all seriousness, this kind of mendacity tends to catch up to a person.
From New York Times • Sep. 1, 2023
As I’ve explained elsewhere, live TV interviews will always favor those who prefer mendacity.
From Slate • May 11, 2023
Truth-defending humans may not have the capacity to effectively push back against the mendacity machine.
From Seattle Times • Apr. 7, 2023
If divorce had presented itself as the dastardly antithesis of all this, it could easily have been cast onto the other pan of the scales, along with betrayal, illness, thieving, assault and mendacity.
From "Atonement" by Ian McEwan
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
