Radiance
WordNet
noun
(1) The quality of being bright and sending out rays of light
(2) The amount of electromagnetic radiation leaving or arriving at a point on a surface
(3) An attractive combination of good health and happiness
"The radiance of her countenance"
WiktionaryText
Noun
- the quality of being radiant, shining, bright or splendid
- the flux of radiation emitted per unit solid angle in a given direction by a unit area of a source