Fluorescence \Flu`o*res"cence\, n. [From Fluor.] (Chemistry,
   Optics)
   A luminescence emitted by certain substances due to the
   absorption of radiation at one wavelength, and the almost
   instantaneous re-emission of radiation at another, usually
   longer wavelength. The re-radiation stops almost as soon as
   the incident radiation is halted, thus distinguishing this
   phenomenon from phosphorescence, in which re-radiation of
   light may continue for some time after the incident radiation
   is halted.

   Note: The color of the radiated light typically differs from
         the apparent color of the material, as when green
         crystals of fluor spar afford blue reflections. It is
         due not to the difference in the color of a distinct
         surface layer, but to the power which the substance has
         of modifying the light incident upon it, by first
         absorbing the light to achieve an excited state, and
         then radiating light to resume the ground energy level.
         The light emitted by fluorescent substances is in
         general of longer wavelength than the incident light.
         The radiation can also be induced by ionizing radiation
         which is not electromagnetic, such as alpha or beta
         rays, and cathode rays. This property is possessed by
         fluorspar, uranium glass, sulphide of calcium, and many
         other substances. It finds use in analytical
         instruments to detect or measure radiation, and in some
         commercial applications.
         [1913 Webster +PJC]

	

	fluorescence
    n 1: light emitted during absorption of radiation of some other
         (invisible) wavelength

	

	28 Moby Thesaurus words for "fluorescence":
   autoluminescence, bioluminescence, cathode luminescence,
   chemicoluminescence, chemiluminescence, corposant,
   crystalloluminescence, double corposant, electroluminescence,
   fata morgana, fox fire, ignis fatuus, luciferase, luciferin,
   luminescence, luminophor, marshfire, noctiluscence, phosphor,
   phosphorescence, photoluminescence, radioluminescence,
   thermoluminescence, tribofluorescence, triboluminescence,
   tribophosphorescence, wisp, witch fire