fallout

1 of 2

noun

fall·​out ˈfȯl-ˌau̇t How to pronounce fallout (audio)
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
expected to be in the States …  , but things fell out otherwiseMark 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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Noun
The shooting occurred on September 19, days after Kimmel’s remarks about the political fallout surrounding the death of activist Charlie Kirk. Amanda Castro, MSNBC Newsweek, 24 Sep. 2025 As Missouri grapples with the fallout from the chaotic special session, the gerrymandered congressional map and the initiative petition overhaul are poised to face fierce resistance over the next several weeks. Kacen Bayless, Kansas City Star, 23 Sep. 2025
Verb
But the game fell out of reach early in front of the second-smallest crowd of the season at Sutter Health Park. Chris Biderman, Sacbee.com, 26 Sep. 2025 Originally released as a cross-trainer in 1999, the Air Max Sunder garnered a cult following but fell out of Nike’s lineup until its return in 2024 (not counting an extremely limited Comme des Garçons collaboration from 2021). Ian Servantes, Footwear News, 24 Sep. 2025 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 29 Sep. 2025.

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

More from Merriam-Webster on fallout

Last Updated: - Updated example sentences
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