Insurrection is curbed by cartel (6)
I believe the answer is:
rising
'insurrection' is the definition.
(I know that insurrection can be written as rising)
'is curbed by cartel' is the wordplay.
'curbed by' is an insertion indicator (I've seen this in other clues).
'cartel' becomes 'ring' (both can mean a criminal group).
'is' inserted within 'ring' is 'RISING'.
(Other definitions for rising that I've seen before include "Approaching the age of" , "Armed revolt against authority" , "A revolt; getting up" , "Sloping up; rebellion" , "Ascending" .)