Fallout describes the consequences that spread outward after something bad happens, especially when those effects reach people who weren't directly involved. When two friends have a huge argument at lunch, the fallout might include other kids taking sides, plans for the weekend getting canceled, and an uncomfortable atmosphere in the whole friend group for days.

The word originally described the radioactive particles that fall from the sky after a nuclear explosion, drifting far beyond the blast site and affecting areas that seemed safe.

You'll hear about political fallout when a scandal damages a leader's reputation and causes problems for their allies too. A company might deal with fallout from a failed product, losing customers and facing angry shareholders. When your school changes a popular policy, teachers might worry about the fallout among students and parents.

The key idea is that fallout reaches beyond the original problem. If you accidentally break your sister's favorite mug, that's a problem. But if she stops talking to you, your parents get involved, and the whole family dinner becomes tense, that's the fallout. The initial event was small, but the consequences rippled outward and affected everyone around.