de·​lir·​i·​um | \di-ˈlir-ē-əm \

Definition 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

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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

What an honor to host @reesewitherspoon for her #whiskeyinateacup book tour tonight at the Silos✨ Despite being deep in baby delirium, Joanna was thrilled to be there. Jessica Leigh Mattern, Country Living, "Joanna Gaines Steps Out for Her First Major Public Appearance Since Giving Birth to Crew," 29 Sep. 2018 Excited delirium is a controversial condition often cited when police use force. Gina Barton, Milwaukee Journal Sentinel, "No discipline likely for West Milwaukee cops who tased man 18 times, police chief says," 27 Apr. 2018 The goal only bought Russia eight minutes of delirium. Joshua Robinson, WSJ, "Russia Is Out of the Russian World Cup," 7 July 2018 Akinfeev guessed right to stop Spain’s third kick from Koke, then produced an incredible stop with his outstretched left cleat to keep out Iago Aspas, sending the stadium – and the country – into delirium. Martin Rogers, USA TODAY, "Whatever happens, Vladimir Putin is winning the World Cup," 1 July 2018 For some on the left and indeed on the right, polarization has become a drug that produces a pleasurable political delirium. Daniel Henninger, WSJ, "Kavanaugh and the Culture Wars," 11 July 2018 Symptoms of heat stroke include high fever; dry, red skin; rapid and weak pulse and breathing; convulsions; and delirium. Scott Dance,, "Maryland health officials report first heat-related death of summer, a Prince George's County man," 20 June 2018 Those Croatian players that could still move ran to their fans once more, the fatigue stripped away by delirium. Rory Smith, New York Times, "Croatia Digs Deeper, Burying England’s World Cup Dreams," 12 July 2018 For the eventual winner, delirium - for the loser, tears and abject misery., "A Nation Erupts: England Penalty Shootout Glory Sends Shockwaves Around the Country," 3 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'delirium.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of delirium

circa 1563, in the meaning defined at sense 1

History and Etymology for delirium

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

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Statistics for delirium

Last Updated

15 Nov 2018

Look-up Popularity

Time Traveler for delirium

The first known use of delirium was circa 1563

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More Definitions for delirium



English Language Learners Definition of delirium

: a mental state in which you are confused and not able to think or speak clearly usually because of fever or some other illness

: a state of wild excitement and great happiness


de·​lir·​i·​um | \di-ˈlir-ē-əm \

Kids Definition of delirium

1 : a condition of mind in which thought and speech are confused usually because of a high fever or other illness

2 : wild excitement


de·​lir·​i·​um | \di-ˈlir-ē-əm \

Medical Definition of delirium 

: a mental disturbance characterized by confusion, disordered speech, and hallucinations

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Comments on delirium

What made you want to look up delirium? Please tell us where you read or heard it (including the quote, if possible).


something that serves to warn or remind

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