The Collaborative International Dictionary of English v.0.48:

Luminary \Lu"mi*na*ry\, n.; pl. Luminaries, [F. luminaire, L.
   luminare a light or lamp, which was lighted in the churches,
   a luminary, fr. lumen, luminis, light, fr. lucere to be
   light, to shine, lux, lucis, light. See Light.]
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   1. Any body that gives light, especially one of the heavenly
      bodies. " Radiant luminary." --Skelton.
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            Where the great luminary . . .
            Dispenses light from far.             --Milton.
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   2. One who illustrates any subject, or enlightens mankind;
      as, Newton was a distinguished luminary.
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