Punished for sunny day (5)
I believe the answer is:
fined
'punished' is the definition.
('fined' can be similar in meaning to 'punished')
'sunny day' is the wordplay.
'sunny' becomes 'fine' (I've seen this before).
'day' becomes 'd'.
'fine'+'d'='FINED'
'for' is the link.
(Other definitions for fined that I've seen before include "Ordered to pay penalty" , "Mulcted" , "Fed in (anag.)" , "Imposed financial penalty on" .)