Radiant woman goes up West (5)
I believe the answer is:
aglow
'radiant' is the definition.
(I've seen this before)
'woman goes up west' is the wordplay.
'woman' becomes 'olga' (**).
'goes up' says the letters should be written backwards.
'west' becomes 'w' ('W' can be a synonym of 'west').
'olga' reversed gives 'aglo'.
'aglo'+'w'='AGLOW'
(Other definitions for aglow that I've seen before include "Smouldering" , "Incandescent" , "Lit up" , "Red-hot" , "Gently radiant" .)