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delirium

American  
[dih-leer-ee-uhm] / dɪˈlɪər i əm /

noun

  • deliriums,
    plural
  • deliria
    plural
  1. Pathology. a more or less temporary disorder of the mental faculties, as in fevers, disturbances of consciousness, or intoxication, characterized by restlessness, excitement, delusions, hallucinations, etc.

  2. a state of violent excitement or emotion.


delirium British  
/ dɪˈlɪrɪəm /

noun

  1. a state of excitement and mental confusion, often accompanied by hallucinations, caused by high fever, poisoning, brain injury, etc

  2. violent excitement or emotion; frenzy

"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

Derived Forms

Inflected Forms

Nouns

Etymology

Origin of delirium

1590–1600; < Latin dēlīrium frenzy, equivalent to dēlīr ( āre ) ( see deliration) + -ium -ium

Explanation

Experiencing delirium? Then you're out of your mind and so excited you're hallucinating. Many things can cause delirium, including illness, high stress, and your team winning the World Series after 100 years of trying. Delirium means “madness” in Latin, and for good reason. Patients with high fevers or who suffer severe trauma might experience a state of delirium, full of mental confusion and maybe a little hysteria. And if you’ve ever stayed up all night writing a paper or working hard to meet some deadline, you’ve probably experienced moments of delirium, where you feel crazed and hallucinatory, fueled by sleep deprivation and too much coffee.

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Vocabulary lists containing delirium

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:

As the Aedes aegypti mosquito expanded its range across more of the Americas, it brought with it the delirium, jaundice, and aching joints of yellow fever.

From Slate ● Aug. 4, 2026

There was delirium when they took an early lead against Germany in their opening game, but it would end in humiliation as the European giants eventually stuck seven past them.

From BBC ● Jun. 21, 2026

The show once referenced a fast-food item, called the Ribwich, that drives Homer to delirium.

From MarketWatch ● Apr. 29, 2026

You can salute Venezuela for a spirited and thrilling victory, and the Venezuelan fans for nine innings of joyful delirium.

From Los Angeles Times ● Mar. 18, 2026

I'm laughing, so hard that I fall onto the ground in a wild delirium, and my cheeks hurt with a delightful pain.

From "What the Night Sings" by Vesper Stamper

The 4th century church father Jerome called them "deliria."

From Time Magazine Archive

Pronounced mental disorder occurs rarely in tuberculosis, according to Ziehen, and leads either to melancholia or to hallucinatory states of excitement, resembling the deliria of exhaustion or inanition.

From The Journal of Abnormal Psychology, Volume 10 by Various

If stupor be a psychobiological reaction, it should occur, occasionally, in organic conditions just as the deliria of typhoid fever may contain many psychogenic elements.

From Benign Stupors A Study of a New Manic-Depressive Reaction Type by John T. (John Thompson) MacCurdy

Before Breuer and Janet, the great psychiatrist Leuret expressed the opinion that even for the deliria of the insane, if we only understood how to interpret them, a meaning could be found.

From A General Introduction to Psychoanalysis by Sigmund Freud

A similar explanation is made readily enough in cases of evident bodily disease, even where mental symptoms are prominent, for it is no longer the custom to speak of demon-possession even in the acute deliria.

From The Journal of Abnormal Psychology, Volume 10 by Various

Critics called the product’s most notable side effect “delirium” and warned that these deliriums could have catastrophic effects on children, the elderly, or the immunocompromised.

From Slate ● Aug. 28, 2021

Is this the book that launched a thousand quips, and stirred the orators to deliriums of denunciation?

From Time Magazine Archive

On the evening of the second day, the girl—the one who Goddard said was so important—came into his room in between deliriums.

From "Scythe" by Neal Shusterman

So is that also, of the lunacy of the King of England, which is a decided fact, notwithstanding all the stuff the English papers publish, about his fevers, his deliriums, &c.

From Memoir, Correspondence, And Miscellanies, From The Papers Of Thomas Jefferson, Volume 2 by Thomas Jefferson Randolph

Thou alone canst comprehend my joys and my deliriums.

From Three short works The Dance of Death, the Legend of Saint Julian the Hospitaller, a Simple Soul. by Gustave Flaubert

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