Official sanction in Mafia technology (4)
I believe the answer is:
fiat
'official sanction' is the definition.
(I've seen this before)
'in mafia technology' is the wordplay.
'in' says the answer is hidden in the clue.
'FIAT' can be found hidden inside 'mafia technology'.
(Other definitions for fiat that I've seen before include "Official sanction" , "mandate" , "Decree; Italian car make" , "Let it be done - it's a Latin order" , "Decree or official permission" .)