delirium

noun

de·​lir·​i·​um di-ˈlir-ē-əm How to pronounce delirium (audio)
Synonyms of delirium
1
: an acute (see acute sense 1a(2)) mental disturbance characterized by confused thinking and disrupted attention usually accompanied by disordered speech and hallucinations
2
: frenzied excitement
… he would stride about his room in a delirium of joy.—Thomas Wolfe
a crowd in a state of delirium

Synonyms of delirium

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Examples of delirium in a Sentence

In her delirium, nothing she said made any sense. shoppers running around in a delirium the day before Christmas
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.
Geriatric ERs also try to counter sensory impairment, another contributor to delirium, by distributing reading glasses and sound-amplifying devices. — Paula Span, Miami Herald, 18 Aug. 2026 Schoenbrun wrote the lyrics, with layers of guitar and orchestral flourishes giving the track a bittersweet, dreamlike quality that fits the film’s collision of desire, fear and delirium. — Spin Staff, SPIN, 14 Aug. 2026 Shah diagnosed delirium and said possible causes included anesthesia, oxygen problems and an elevated heart rate. — Sarah Rumpf-Whitten, FOXNews.com, 4 Aug. 2026 Symptoms of this condition include delirium, seizures, an abnormal heart rhythm, hyperthermia, coma and death. — Andrew Yockey, The Conversation, 24 July 2026 See All Example Sentences for delirium

Word History

Etymology

Latin, from delirare to be crazy, literally, to leave the furrow (in plowing), from de- + lira furrow — more at learn

First Known Use

circa 1563, in the meaning defined at sense 1

Time Traveler
The first known use of delirium was circa 1563

Phrases Containing delirium

Rhymes for delirium

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Browse Nearby Words

delirious
delirium
delirium tremens
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Cite this Entry

“Delirium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/delirium. Accessed 24 Aug. 2026.

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Kids Definition

delirium

noun
de·​lir·​i·​um di-ˈlir-ē-əm How to pronounce delirium (audio)
1
: a mental disturbance marked by confusion, disturbed speech, and hallucinations
2
: wild excitement

Medical Definition

delirium

noun
de·​lir·​i·​um di-ˈlir-ē-əm How to pronounce delirium (audio)
: an acute (see acute sense 2b(1)) mental disturbance characterized by confused thinking and disrupted attention usually accompanied by disordered speech and hallucinations

More from Merriam-Webster on delirium

Nglish: Translation of delirium for Spanish Speakers

Britannica.com: Encyclopedia article about delirium

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