Also in candy (3)
I believe the answer is:
and
'also' is the definition.
(thesaurus)
'in candy' is the wordplay.
'in' says the answer is hidden in the clue.
'AND' is hidden within 'candy'.
(Other definitions for and that I've seen before include "& 18 You bet!" , "Joining word" , "Most-used conjunction in English" , "It's used to connect words, clauses or sentences" , "it needs wholly positive input for positive result" .)