Island in Cuba, lively (4)
I believe the answer is:
bali
'island' is the definition.
(Indonesian island)
'in cuba lively' is the wordplay.
'in' indicates the answer is hidden within the clue.
'BALI' is hidden in the letters of 'cuba lively'.
(Other definitions for bali that I've seen before include "Island in Indonesia" , "Indonesian island, east of Java" , "Javanese island" , "Middle East country" , "Holiday island to the east of Java" .)