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Synonyms

irrationality

American  
[ih-rash-uh-nal-i-tee] / ɪˌræʃ əˈnæl ɪ ti /

noun

  • irrationalities
    plural
  1. the quality or condition of being irrational.

  2. an irrational, illogical, or absurd action, thought, etc.


irrationality British  
/ ɪˌræʃəˈnælɪtɪ /

noun

  1. the state or quality of being irrational

  2. irrational thought, action, or behaviour

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

Noun Inflected Forms


Etymology

Origin of irrationality

First recorded in 1560–70; irrational + -ity


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.

See Examples For:

“Today’s lawsuit continues the absurdity and irrationality that the industry has come to expect from the defunct organization formerly known as the HFPA.”

From Los Angeles Times ● Jul. 28, 2026

Options remain the best way to monetize investor irrationality and emotional dysregulation.

From Barron's ● Mar. 11, 2026

Bennett argued presciently that by kowtowing to radicals, “a great university was brought low by the very forces which modern universities came into being to oppose: ignorance, irrationality and intimidation.”

From The Wall Street Journal ● Feb. 17, 2026

JPMorgan Chase boss Jamie Dimon said some of the money invested in AI would "probably be lost", while Google parent company Alphabet's chief executive Sundar Pichai said there was some "irrationality" in the AI boom.

From BBC ● Jan. 27, 2026

The possibility of social irrationality resting on a base of individual rationality is suggested by a slight variant of Condorcet’s original example.

From "Innumeracy: Mathematical Illiteracy and Its Consequences" by John Allen Paulos

But they can newly explain so many of the irrationalities that are directly a product of the digital age.

From Los Angeles Times ● Apr. 11, 2024

Well, all the reading I do is sort of aimed at the general mission of being more compassionate toward other people's irrationalities and skeptical of my own.

From Salon ● Apr. 9, 2024

In this way, Kirsch accepts the standard story about modernity: that ours is an era of “disenchantment” in which the old myths and irrationalities have been crushed under the boot heel of enlightened techno-science.

From Slate ● Jan. 26, 2023

The crux of the problem, as Cowen points out, is that it’s nearly impossible to understand irrationalities without taking advantage of them.

From Scientific American ● Apr. 27, 2012

One of the unfair irrationalities of love is that it may, at first, be attracted by the defects of the beloved, and later repelled by them.

From The Vehement Flame by Margaret Wade Campbell Deland

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