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

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

From MarketWatch • Apr. 1, 2026

“A relatively quick end to the conflict would limit the economic fallout of course, but concerns about longer-lasting effects are clearly starting to affect the mood in Europe,” he said.

From The Wall Street Journal • Mar. 30, 2026

"The fallout of this is that we could experience sharper price spikes, broader inflation pain, and deeper recession risks, especially in import-heavy Asia," she continued.

From BBC • Mar. 30, 2026

"The market is now reacting to higher crude pricing and towards the fallout in the economic consequences," wrote Pepperstone's Chris Weston.

From Barron's • Mar. 30, 2026

The cometary impact and fireball would simulate all effects of a one- megaton nuclear burst, including the mushroom cloud, with two exceptions: there would be no gamma radiation or radioactive fallout.

From "Cosmos" by Carl Sagan