Glitter has added light (3)
I believe the answer is:
lit
'light' is the definition.
(similar in meaning)
'glitter has added' is the wordplay.
'LIT' is hidden within the letters.
However, I am uncertain how the hidden word is indicated.
Can you help me to learn more?
(Other definitions for lit that I've seen before include "Set fire to" , "fine writing in condensed form" , "Ignited, say cigarette" , "Creative writing, in short" , "Illuminated" .)