Fool in turn gets to leave out sweet (7)
I believe the answer is:
gumdrop
'sweet' is the definition.
(gumdrop is a kind of sweet)
'fool in turn gets to leave out' is the wordplay.
'fool' becomes 'mug' (synonyms).
'in turn' is a reversal indicator (letters turning around).
'gets' says to put letters next to each other.
'to leave out' becomes 'drop' (synonyms).
'mug' backwards is 'gum'.
'gum'+'drop'='GUMDROP'
(Other definitions for gumdrop that I've seen before include "Gelatinous type of sweet" , "Type of jelly sweet" , "It may be sucked" , "Firm jelly sweet" , "Small sweet (goody goody!)" .)