If you're visiting your friend in California and her house starts to shake, you might be experiencing an earthquake, which is the shaking of the surface of the earth that happens when there's movement deep underground.

Earthquake is one of those words that means exactly what it sounds like: the earth is quaking. Earthquakes happen along "fault lines," the places where the big plates of the earth meet and rub up against each other during volcanic activities. We also use earthquake metaphorically, to talk about something that causes a violent upheaval.

Definitions of earthquake
  1. noun
    shaking and vibration at the surface of the earth resulting from underground movement along a fault plane of from volcanic activity
    synonyms: quake, seism, temblor
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    seismic disturbance, shock
    an instance of agitation of the earth's crust
    earth tremor, microseism, tremor
    a small earthquake
    seaquake, submarine earthquake
    an earthquake at the sea bed
    a tremor (or one of a series of tremors) occurring after the main shock of an earthquake
    a tremor preceding an earthquake
    type of:
    geological phenomenon
    a natural phenomenon involving the structure or composition of the earth
  2. noun
    a disturbance that is extremely disruptive
    “selling the company caused an earthquake among the employees”
Word Family

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