[1] : The Collaborative International Dictionary of English v.0.48

luminousness \lu"minousness\ n.
   the quality of being luminous; emitting or reflecting light.

   syn: luminosity, luminance, light.
        wordnet 1.5

[2] : The Collaborative International Dictionary of English v.0.48

luminous \lu"minous\, a. l. luminosus, fr. lumen light: cf. f.
   lumineux. see luminary, illuminate.
   1913 webster
   1. shining; emitting or reflecting light; brilliant; bright;
      as, the is a luminous body; a luminous color.
      1913 webster

            fire burneth wood, making it . . . luminous.
                                                  --bacon.
      1913 webster

            the mountains lift . . . their lofty and luminous
            heads.                                --longfellow.
      1913 webster

   2. illuminated; full of light; bright; as, many candles made
      the room luminous.
      1913 webster

            up the staircase moved a luminous space in the
            darkness.                             --longfellow.
      1913 webster

   3. enlightened; intelligent; also, clear; intelligible; as, a
      luminous mind. " luminous eloquence." --macaulay. " a
      luminous statement." --brougham.
      1913 webster

   luminous paint, a paint made up with some phosphorescent
      substance, as sulphide of calcium, which after exposure to
      a strong light is luminous in the dark for a time.
      1913 webster

   syn: lucid; clear; shining; perspicuous.
        1913 webster -- lu"minously, adv. --
        lu"minousness, n.
        1913 webster
see also:
luminary illuminate luminous paint lu"minously lu"minousness 

[3] : WordNet (r) 2.0

luminousness
     n : the quality of being luminous; emitting or reflecting light;
         "its luminosity is measured relative to that of our sun"
         syn: luminosity, brightness, brightness level, luminance,
          light
see also:
luminosity brightness brightness level luminance light 

Luminousness >> L Words
Luminousness, definition of term: Luminousness
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