fall·out | \ˈfȯl-ˌau̇t \

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


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

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Examples of fallout in a Sentence


concerned about the possible political fallout from the scandal


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.
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Recent Examples on the Web: Noun

Escalating tensions with the U.S. exacerbated growing concerns about the fallout from a slowing Chinese economy, fueling a climate of uncertainty. Ian Mount, Fortune, "Chinese Smartphone Maker Xiaomi’s Monster IPO Flops on Its First Day of Trading," 9 July 2018 The fallout from that privacy scandal has been enormous – but how does Google's breach compare? CBS News, "Google reportedly allows apps to scan some people's Gmail inboxes," 3 July 2018 The fallout was swift the morning after German Chancellor Angela Merkel reached an uneasy late-night immigration compromise with hard-line coalition allies, an agreement that appears to have saved her fragile government, at least for now. James Mcauley, latimes.com, "Pressure mounts as Germany's Merkel fine-tunes immigration compromise," 3 July 2018 The president’s public attack on Harley is likely to further frustrate Republicans, who have been increasingly worried about the fallout from his trade war. New York Times, "Trump Threatens Harley-Davidson, Saying It ‘Surrendered’," 26 June 2018 Shares of Facebook are now trading higher than before the massive data leak, but investors remain concerned about the potential fallout on the advertising business from the relentlessly negative publicity. Jessica Guynn, USA TODAY, "At Facebook annual meeting, investor warns Mark Zuckerberg about 'corporate dictatorship'," 31 May 2018 Business leaders, meanwhile, continued to sound the alarm about the potential economic fallout from tariffs, with the president and CEO of the U.S. Chamber of Commerce raising the specter of a global trade war. Ken Thomas, baltimoresun.com, "Trump announces stiff trade tariffs, unswayed by warnings," 8 Mar. 2018 Local centers are dealing with the fallout in their own ways. Andy Newman, New York Times, "The ‘King’ of Shambhala Buddhism Is Undone by Abuse Report," 11 July 2018 Such exports are a growing phenomenon in the United States, a traditional importer of natural gas before the fracking boom, and a growing source of energy for Japan, which is still dealing with fallout from the Fukushima Daiichi nuclear disaster. Kevin Rector, baltimoresun.com, "High-speed rail, liquefied natural gas, and the connections between Maryland and Japan," 10 July 2018

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.

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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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Statistics for fallout

Last Updated

11 Oct 2018

Look-up Popularity

Time Traveler for fallout

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

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More Definitions for fallout



English Language Learners Definition of fallout

: the radioactive particles that are produced by a nuclear explosion and that fall through the atmosphere

: a bad effect or result of something


fall·out | \ˈfȯl-ˌau̇t \

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 \

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

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Comments on fallout

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


evasion of direct action or statement

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