A bit of syrup in a cola daiquiri (a rum cocktail) (4,6)
I believe the answer is:
Here is my best explanation:
'a rum cocktail' is the definition.
(I've seen this before)
'a bit of syrup in a cola daiquiri' is the subsidiary indication.
'a bit of' indicates a hidden word.
'pinacolada' can be found hidden inside 'syrup in a cola daiquiri'.
(Other definitions for pina colada that I've seen before include "Pineapple cocktail", "rum-based potation", "Rum cocktail", "Cocktail of rum, pineapple juice and coconut", "Drink made of pineapple juice, coconut cream and rum", "alcoholic one", "drink" and "Perhaps contents of cocktail glass".)