Fall out or fallout?
fall out is a noun meaning “Synonym of falling out (“rift following a disagreement or quarrel”)”; fallout is a noun meaning “The event of small airborne particles falling to the ground in significant…”. fall out is written as two words and fallout as one word; they are used differently.
What is the difference between fall out and fallout?
| fall out | fallout | |
|---|---|---|
| Part of speech | noun, verb | noun |
| Meaning | Synonym of falling out (“rift following a disagreement or quarrel”) To come out of something by falling To cease to be on friendly terms | The event of small airborne particles falling to the ground in significant quantities as a result of major industrial activity, volcano eruption, sandstorm… The particles themselves |
| Example | We had a fall out, couldn't come to terms and haven't talked since | On 26 April 1986 the reactor number four at the Chernobyl Nuclear Power Plant located in the Soviet Union near Pripyat in Ukraine exploded.… |
| Forms | fall-outs | fallouts |
| Pronunciation | not recorded | /ˈfɔːlaʊt/ /ˈfɔlˌaʊt/ |
| In writing | not counted (the list counts single words) | 4.9 times per million words |
Sources: fall out and fallout in the English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0); written frequency: wordfreq 3.1 (a 2021 snapshot of Wikipedia, subtitles, news, books, web text and social media).
Every current meaning of fall out and fallout
fall out
- 1
Synonym of falling out (“rift following a disagreement or quarrel”)
We had a fall out, couldn't come to terms and haven't talked since
- 2
To come out of something by falling
I opened the cupboard and a can fell out onto my foot
- 3
Alternative spelling of fallout
- 4
To cease to be on friendly terms
Dave and I fell out after a long argument
- 5
To leave one's place in the current formation of ranks in order to take one's place in a new formation
- 6
To leave one's current location to report for duty at a new location
The company fell out for an artillery drill
- 7
To pass out
- 8
datedTo turn out, happen
I expected to be in the States long before this, but things fell out otherwise
fallout
- 1
The event of small airborne particles falling to the ground in significant quantities as a result of major industrial activity, volcano eruption, sandstorm, nuclear explosion, etc
- 2
The particles themselves
On 26 April 1986 the reactor number four at the Chernobyl Nuclear Power Plant located in the Soviet Union near Pripyat in Ukraine exploded. Further explosions and the resulting…
- 3
A negative side effect; an undesirable or unexpected consequence
Psychological fallout in the shadow of terrorism
- 4
An impromptu guest used to fill in for another guest spot who is a no-show or who has cancelled last minute
Source: the English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0); obsolete, archaic, dialect and rare senses left out.
Which is more common, fall out or fallout?
fall out is a phrase, which the list of single words does not count; fallout 4.9 times per million words.
Source: written frequency: wordfreq 3.1 (a 2021 snapshot of Wikipedia, subtitles, news, books, web text and social media).
How many people search fall out vs fallout?
“fall out vs fallout” is searched about 10 times a month on Google and 10 on Bing in the United States. Google counts close variants of a query together (“fallout vs fall out”, “fall out or fallout”).
Sources: Google Ads keyword data through DataForSEO and Microsoft Advertising keyword data through DataForSEO, the average month from September 2025 to August 2026.