Source : Webster's Revised Unabridged Dictionary (1913)

Earthquake \Earth"quake`\, n.
   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 \Earth"quake`\, a.
   Like, or characteristic of, an earthquake; loud; starling.

         The earthquake voice of victory.         --Byron.

Source : WordNet®

earthquake
     n 1: shaking and vibration at the surface of the earth resulting
          from underground movement along a fault plane of from
          volcanic activity [syn: {quake}, {temblor}, {seism}]
     2: a disturbance that is extremely disruptive; "selling the
        company caused an earthquake among the employees"

Source : Free On-Line Dictionary of Computing

earthquake
     
        (IBM) The ultimate real-world shock test for computer
        hardware.  Hackish sources at {IBM} deny the rumor that the
        San Francisco Bay Area quake of 1989 was initiated by the
        company to test quality-assurance procedures at its California
        plants.
     
        [{Jargon File}]
     
        (1995-04-22)