Thirty days in Capri left (5)
I believe the answer is:
april
'thirty days' is the definition.
(I've seen this before)
'in capri left' is the wordplay.
'in' indicates a hidden word.
'APRIL' is hidden in the letters of 'capri left'.
(Other definitions for april that I've seen before include "All in the ..... evening (song)" , "Calendar month" , "''... is the cruellest month''(Elliot)" , "''... is the cruellest month'' (TS Eliot)" , "Thirty days in spring" .)