fall·​out | \ ˈfȯl-ˌau̇t How to pronounce fallout (audio) \

Definition of fallout

 (Entry 1 of 2)

1a : the often radioactive particles stirred up by or resulting from a nuclear explosion and descending through the atmosphere also : other polluting particles (such as volcanic ash) descending likewise
b : descent (as of fallout) through the atmosphere
2 : a secondary and often lingering effect, result, or set of consequences have to take a position and accept the political fallout— Andy Logan

fall out

fell out; fallen out; falling out; falls out

Definition of fall out (Entry 2 of 2)

intransitive verb

1 : quarrel also : to cut off relations over a quarrel former friends who have fallen out
2 : turn out, happen expected to be in the States …  , but things fell out otherwise— Mark Twain
3a : to leave one's place in the ranks
b : to leave a building in order to take one's place in a military formation

Examples of fallout in a Sentence

Noun concerned about the possible political fallout from the scandal Verb club members were soon falling out about how to spend the money they'd made washing cars I had planned to have a sports career, but things fell out otherwise.
Recent Examples on the Web: Noun Amid the fallout from the convention, Matt Maddock, a Republican state representative whom Mr. Trump had supported to become speaker next year, was pushed out of the House Republican caucus this week. New York Times, 28 Apr. 2022 Le Pen has sought to appeal to working class voters struggling with surging prices amid the fallout of Russia’s war in Ukraine, an approach that even Macron acknowledged has found resonance in the wider public. NBC News, 24 Apr. 2022 Le Pen's campaign this time has sought to appeal to voters struggling with surging food and energy prices amid the fallout of Russia's war in Ukraine. Sylvie Corbet, ajc, 23 Apr. 2022 But his final hearing as chair, amid the fallout from the 2020 election, was filled with acrimony. Bill Glauber, Milwaukee Journal Sentinel, 21 Apr. 2022 Posting a nearly 13-minute video on Instagram on New Year's Day, Baldwin spoke directly to the camera and shared his hopes for the coming year amid the ongoing fallout from the tragic shooting. Nicholas Rice, PEOPLE.com, 9 Jan. 2022 But another motivation is also slowly emerging: Overturning Roe could have devastating political fallout for Republicans. Alex Shephard, The New Republic, 9 May 2022 If the Supreme Court does, in fact, overturn or substantially curtail Roe v. Wade and Casey v. Planned Parenthood, the GOP will be unprepared to deal with the political fallout. Charlie Dent, CNN, 9 May 2022 Ohio's primary season is over, but the ongoing political fallout of former President Donald Trump's influence across the state is already brewing ahead of November in the 9th Congressional District. Rick Klein, ABC News, 6 May 2022 See More

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

First Known Use of fallout


1946, in the meaning defined at sense 1a


15th century, in the meaning defined at sense 1

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The first known use of fallout was in the 15th century

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Dictionary Entries Near fallout

fallopian tube


fall out

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Statistics for fallout

Last Updated

24 May 2022

Cite this Entry

“Fallout.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fallout. Accessed 26 May. 2022.

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More Definitions for fallout


fall·​out | \ ˈfȯl-ˌau̇t How to pronounce fallout (audio) \

Kids Definition of fallout

1 : the usually radioactive particles falling through the atmosphere as a result of a nuclear explosion
2 : the bad result of something He suffered the fallout from his poor decision.


fall·​out | \ ˈfȯ-ˌlau̇t How to pronounce fallout (audio) \

Medical Definition of fallout

1 : the often radioactive particles stirred up by or resulting from a nuclear explosion and descending through the atmosphere also : other polluting particles (as volcanic ash) descending likewise
2 : descent (as of fallout) through the atmosphere

More from Merriam-Webster on fallout

Nglish: Translation of fallout for Spanish Speakers

Britannica English: Translation of fallout for Arabic Speakers

Britannica.com: Encyclopedia article about fallout


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