Wind bit of orange zest (5)
I believe the answer is:
gusto
'zest' is the definition.
(synonyms)
'wind bit of orange' is the wordplay.
'wind' becomes 'gust' (gust of wind).
'bit of' indicates taking the first letters.
The first letter of 'orange' is 'o'.
'gust'+'o'='GUSTO'
(Other definitions for gusto that I've seen before include "Obvious enthusiasm" , "Zest and enjoyment in doing something" , "Got us with great enjoyment" , "Great enjoyment, vigour" , "Relish; vigour" .)