Juice of various apples (3)
I believe the answer is:
sap
'juice' is the definition.
(thesaurus)
'of various apples' is the wordplay.
'of' indicates the answer is hidden within the clue.
'SAP' is hidden within 'various apples'.
(Other definitions for sap that I've seen before include "dig tunnels" , "Drain of energy" , "Watery substance in a plant" , "Cosh; plant's juice" , "trench used in siege" .)