Smart operation involving deception (5)
I believe the answer is:
sting
I believe this clue is a double definition.
'smart' is the first definition.
(both can mean to burn or hurt)
'operation involving deception' is the second definition.
(eg a police sting)
(Other definitions for sting that I've seen before include "Goad" , "Bee's weapon" , "Entrapment operation; sharp pain" , "Con: leader singer of Police" , "Pole from Glasgow" .)