View duck on the wing (7)
I believe the answer is:
opinion
'view' is the definition.
(synonyms)
'duck on the wing' is the wordplay.
'duck' becomes 'o' (resembles zero - 'duck' in cricket).
'on' is a charade indicator (letters next to each other).
'the wing' becomes 'pinion' ('pinion' can be a synonym of 'wing').
'o'+'pinion'='OPINION'
(Other definitions for opinion that I've seen before include "Point of view or thought on something" , "thinking" , "school of thought" , "View, barrister's advice" , "Personal view" .)