What does "earthquake" mean?

Earthquake: A shaking, trembling, or concussion of the earth, due to subterranean causes, often accompanied by a rumbling noise. The wave of shock sometimes traverses half a hemisphere, destroying cities and many thousand lives; -- called also earthdin, earthquave, and earthshock. Earthquake alarm, a bell signal constructed to operate on the theory that a few seconds before the occurrence of an earthquake the magnet temporarily loses its power.

Additional senses

  1. 2.Like, or characteristic of, an earthquake; loud; starling. The earthquake voice of victory. Byron.

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