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fallout

n.
US //ˈfɔˌɫaʊt// UK //fˈɔːlaʊt// fall·out
  1. 1 radioactive dust (n.)
    B2 Upper Intermediate Technical Science

    the dangerous radioactive dust that falls from the sky after a nuclear explosion.

    radioactive particles that are carried into the atmosphere after a nuclear explosion and gradually fall back to earth.

    Example

    The scientists measured the level of radioactive fallout in the soil after the accident.

    Example

    Prevailing winds carried the radioactive fallout hundreds of miles from the blast site, contaminating agricultural land across several borders.

    Usage

    Usually uncountable when referring to the material itself.
  2. 2 bad consequences (n.)
    B2 Upper Intermediate

    the unpleasant results or effects that follow a bad situation or argument.

    the adverse results or incidental consequences of an event, especially a political or social scandal.

    Example

    The company is still dealing with the political fallout from the CEO's resignation.

    Example

    The diplomatic fallout from the failed negotiations led to a cooling of relations between the two neighbouring countries for several years.

    Usage

    Often used with the preposition 'from'.
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  1. 3 television guest (n.)
    C2 Proficiency Technical Theatre

    a person who is asked to appear on a show at the last minute because someone else cancelled.

    a substitute guest used to fill a broadcasting slot when the original participant is unavailable.

    Example

    The talk show host had to find a fallout when the lead actor missed his flight.

    Example

    The production assistant kept a list of reliable fallouts who could be at the studio within an hour if a primary guest cancelled.

    Teacher's tip

    This is a highly specialised industry term; most English speakers will only know the 'consequences' or 'nuclear' meanings.
Origin

Deverbal from fall out; fall + out.

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