Doze during picnic at Naples (6)
I believe the answer is:
catnap
'doze' is the definition.
(I have seen 'Brief doze' mean 'catnap' so perhaps 'doze' could also mean 'catnap')
'during picnic at naples' is the wordplay.
'during' indicates the answer is hidden within the clue.
'CATNAP' is hidden within 'picnic at naples'.
(Other definitions for catnap that I've seen before include "(Tom's) snooze?" , "For a rest" , "Brief time out" , "Short sleep" , "little snooze" .)