doomsday

American  

[doomz-dey] / ˈdumzˌdeɪ /

noun

1. Theology. the day of the Last Judgment, at the end of the world.

2. any day of judgment or sentence.

3. nuclear destruction of the world.

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adjective

1. given to or marked by forebodings or predictions of impending calamity; especially concerned with or predicting future universal destruction.

   the doomsday issue of all-out nuclear war.

2. capable of causing widespread or total destruction.

   doomsday weapons.

doomsday British  

/ ˈduːmzˌdeɪ /

noun

1. (sometimes capital) the day on which the Last Judgment will occur

2. any day of reckoning

3. (modifier) characterized by predictions of disaster

   doomsday scenario

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Etymology

Origin of doomsday

First recorded before 1000; Middle English domes dai, Old English dōmesdæg “Judgment Day”; equivalent to doom ( def. ) + 's ¹ ( def. ) + day ( def. )

Explanation

In many religions, doomsday is the end of the world and the moment of final judgment. In your everyday life, doomsday might be the date of the final exam in your math class. Doomsday means utter catastrophe, in both religious and secular contexts. Many faiths believe in a literal doomsday, when life as we know it will come to an end. For centuries people have attempted to predict when this will occur, with the most recent guesses including 2011, 2012, and 2021. Generally, a doomsday scenario is any event that could cause human extinction, like catastrophic climate change or an asteroid impact. The Germanic root of doomsday means "judgment day."

Example Sentences

To know what this means for you in real dollar terms, you need a sophisticated calculator that can run a doomsday scenario for you against your retirement plan.

From MarketWatch • Jun. 9, 2026

For all the doomsday predictions that AI will make management consultants obsolete, Boston Consulting Group CEO Christoph Schweizer has this retort: Look at the business.

From The Wall Street Journal • May 28, 2026

Derek Muller, an election law expert, suggests that scenario is little more than a fever dream of doomsday devotees and overly nervous Nellies.

From Los Angeles Times • Apr. 26, 2026

"We've had this doomsday scenario mentioned on multiple occasions over the last 15 to 20 years," added Maguire.

From BBC • Apr. 5, 2026

Doomsday scenarios are only fun when doomsday is just a hypothetical.

From "Dry" by Neal Shusterman and Jarrod Shusterman