Source : Webster's Revised Unabridged Dictionary (1913)

Pan \Pan\, n. [OE. panne, AS. panne; cf. D. pan, G. pfanne, OHG.
   pfanna, Icel., Sw., LL., & Ir. panna, of uncertain origin;
   cf. L. patina, E. paten.]
   1. A shallow, open dish or vessel, usually of metal, employed
      for many domestic uses, as for setting milk for cream, for
      frying or baking food, etc.; also employed for various
      uses in manufacturing. ``A bowl or a pan.'' --Chaucer.

   2. (Manuf.) A closed vessel for boiling or evaporating. See
      {Vacuum pan}, under {Vacuum}.

   3. The part of a flintlock which holds the priming.

   4. The skull, considered as a vessel containing the brain;
      the upper part of the head; the brainpan; the cranium.
      --Chaucer.

   5. (C?rp.) A recess, or bed, for the leaf of a hinge.

   6. The hard stratum of earth that lies below the soil. See
      {Hard pan}, under {Hard}.

   7. A natural basin, containing salt or fresh water, or mud.

   {Flash in the pan}. See under {Flash}.

   {To savor of the pan}, to suggest the process of cooking or
      burning; in a theological sense, to be heretical.
      --Ridley. Southey.

Flash \Flash\, n.; pl. {Flashes}.
   1. A sudden burst of light; a flood of light instantaneously
      appearing and disappearing; a momentary blaze; as, a flash
      of lightning.

   2. A sudden and brilliant burst, as of wit or genius; a
      momentary brightness or show.

            The flash and outbreak of a fiery mind. --Shak.

            No striking sentiment, no flash of fancy. --Wirt.

   3. The time during which a flash is visible; an instant; a
      very brief period.

            The Persians and Macedonians had it for a flash.
                                                  --Bacon.

   4. A preparation of capsicum, burnt sugar, etc., for coloring
      and giving a fictious strength to liquors.

   {Flash light}, or {Flashing light}, a kind of light shown by
      lighthouses, produced by the revolution of reflectors, so
      as to show a flash of light every few seconds, alternating
      with periods of dimness. --Knight.

   {Flash in the pan}, the flashing of the priming in the pan of
      a flintlock musket without discharging the piece; hence,
      sudden, spasmodic effort that accomplishes nothing.

Source : WordNet®

flash in the pan
     n : someone who enjoys transient success but then fails