Lawlessness (7)
'lawlessness' is the definition.
(synonyms)
This is the entire clue.
(Other definitions for anarchy that I've seen before include "Collapse of order, rule" , "State of civil disorder" , "without structure" , "State of lawlessness and disorder" , "Society without government or law, chaos" .)
(Other definitions for rioting that I've seen before include "Disturbance of the peace" , "Running violently wild" , "Running wild in groups and causing harm" , "Causing a violent disturbance" , "causing uproar" .)