fallout

American  

[fawl-out] / ˈfɔlˌaʊt /

Or fall-out

noun

1. the settling to the ground of airborne particles ejected into the atmosphere from the earth by explosions, eruptions, forest fires, etc., especially such settling from nuclear explosions radioactive fallout.

2. the particles themselves.

3. an unexpected or incidental effect, outcome, or product.

   the psychological fallout of being obese.

4. effects; results.

   emotional fallout from a divorce.

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fallout British  

/ ˈfɔːlˌaʊt /

noun

1. the descent of solid material in the atmosphere onto the earth, esp of radioactive material following a nuclear explosion

2. any solid particles that so descend

3. informal side-effects; secondary consequences

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verb

1. informal to quarrel or disagree

2. (intr) to happen or occur

3. military to leave a parade or disciplinary formation

1. military the order to leave a parade or disciplinary formation

Etymology

Origin of fallout

First recorded in 1945–50; noun use of verb phrase fall out

Example Sentences

But for now the primary fallout from the tariffs in the US has been business strains and higher prices for consumers.

From BBC • Apr. 2, 2026

Unlike the enforced calmness and walking pace associated with fire drills, we were encouraged to run, not walk, to our designated fallout area—all the while covering our faces to protect from flying glass.

From The Wall Street Journal • Apr. 1, 2026

The company was also struggling to manage the fallout from CEO Elon Musk’s role leading the U.S.

From MarketWatch • Apr. 1, 2026

Earlier this month, presidential spokesman Prasetyo Hadi said the government was seeking to set aside as much as 80 trillion rupiah to shield its economy from the Middle East fallout, without disclosing further details.

From Barron's • Mar. 31, 2026

Strauss’s words created alarm over the prospect of nuclear holocaust without laying to rest the public’s anxiety about fallout.

From "Big Science" by Michael Hiltzik