Brilliance (5)
'brilliance' is the definition.
(eclat means brilliance or flair)
This is the entire clue.
(Other definitions for eclat that I've seen before include "Fame -- style" , "French renown" , "Ceremonial elegance and splendour" , "French social distinction or success" , "great success" .)
'brilliance' is the definition.
(I have seen 'Brilliance of glow ' mean 'radiance' so perhaps 'brilliance' could also mean 'radiance')
This is all the clue.
(Other definitions for radiance that I've seen before include "Refulgence" , "Great joy" , "This light" , "Glow (of good health?)" , "Luminous state" .)