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seismic

adj.
US //ˈsaɪzmɪk// UK //sˈaɪzmɪk// seis·mic
  1. 1 related to earthquakes (adj.)
    B2 Upper Intermediate Technical Science

    related to or caused by earthquakes and the way the ground moves.

    relating to or caused by earthquakes or other vibrations of the earth and its crust.

    Example

    The city is located in a seismic zone where small earthquakes are common.

    Example

    Seismic sensors placed along the fault line detected subtle tremors that preceded the major earthquake by several hours.

    Usage

    Usually placed before the noun it modifies.

  2. 2 huge and impactful (adj.)
    C1 Advanced Academic

    having a very big, important, or sudden effect on a situation.

    denoting an event or change of enormous proportions or having a highly significant impact.

    Example

    The invention of the smartphone caused a seismic shift in how we communicate.

    Example

    The sudden collapse of the major investment bank sent seismic shocks through the global financial markets, leading to a decade of instability.

    Teacher's tip

    This figurative use is very common in journalism and academic writing to describe social or political changes.

Origin

Based on Ancient Greek σεισμός (seismós, “shaking, earthquake”) + -ic, equivalent to seismo- + -ic.

Idioms1 entry

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