fallout

1 of 2

noun

fall·​out ˈfȯl-ˌau̇t How to pronounce fallout (audio)
Synonyms of falloutnext
1
a
: 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 falloutAndy Logan

fall out

2 of 2

verb

fell out; fallen out; falling out; falls out

intransitive verb

1
: quarrel
also : to cut off relations over a quarrel
former friends who have fallen out
2
: turn out, happen
I expected to be in the States …, but things fell out otherwise.Mark Twain
3
a
: 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
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Noun
The ensuing fallout— which came just as the department cleared all but one benchmark — led multiple members of OPD’s top command staff to be disciplined, while numerous criminal cases were dismissed or overturned, including at least three murder convictions. Jakob Rodgers, Mercury News, 28 May 2026 One of the more amusing parts of the fallout from Amanda Batula and West Wilson’s relationship announcement has been the race among cast members and corporations to cash in on it. Rebecca Jennings, Vulture, 27 May 2026
Verb
From there, the only way for his glove to go was up and through the slider that fell out of the strike zone as the Dominican Republic’s Geraldo Perdomo stopped his swing. Maddie Lee, Los Angeles Times, 29 May 2026 There were idols everywhere and advantages practically falling out of trees. Daniel Fienberg, HollywoodReporter, 28 May 2026 See All Example Sentences for fallout

Word History

First Known Use

Noun

1946, in the meaning defined at sense 1a

Verb

15th century, in the meaning defined at sense 1

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

Browse Nearby Words

Cite this Entry

“Fallout.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fallout. Accessed 30 May. 2026.

Kids Definition

fallout

1 of 2 noun
fall·​out ˈfȯ-ˌlau̇t How to pronounce fallout (audio)
: the often radioactive particles that are stirred up by or result from a nuclear explosion and descend through the atmosphere

fall out

2 of 2 verb
(ˈ)fȯ-ˈlau̇t
1
: to have a quarrel
2

Medical Definition

fallout

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