Source : Webster's Revised Unabridged Dictionary (1913)

Fault \Fault\, n.
   1. (Elec.) A defective point in an electric circuit due to a
      crossing of the parts of the conductor, or to contact with
      another conductor or the earth, or to a break in the
      circuit.

   2. (Geol. & Mining) A dislocation caused by a slipping of
      rock masses along a plane of facture; also, the dislocated
      structure resulting from such slipping.

   Note: The surface along which the dislocated masses have
         moved is called the

   {fault plane}. When this plane is vertical, the fault is a

   {vertical fault}; when its inclination is such that the
      present relative position of the two masses could have
      been produced by the sliding down, along the fault plane,
      of the mass on its upper side, the fault is a

   {normal}, or {gravity}, {fault}. When the fault plane is so
      inclined that the mass on its upper side has moved up
      relatively, the fault is then called a

   {reverse} (or {reversed}), {thrust}, or {overthrust},
   {fault}. If no vertical displacement has resulted, the fault
      is then called a

   {horizontal fault}. The linear extent of the dislocation
      measured on the fault plane and in the direction of
      movement is the

   {displacement}; the vertical displacement is the

   {throw}; the horizontal displacement is the

   {heave}. The direction of the line of intersection of the
      fault plane with a horizontal plane is the

   {trend} of the fault. A fault is a

   {strike fault} when its trend coincides approximately with
      the strike of associated strata (i.e., the line of
      intersection of the plane of the strata with a horizontal
      plane); it is a

   {dip fault} when its trend is at right angles to the strike;
      an

   {oblique fault} when its trend is oblique to the strike.
      Oblique faults and dip faults are sometimes called

   {cross faults}. A series of closely associated parallel
      faults are sometimes called

   {step faults} and sometimes

   {distributive faults}.