Anarchic (7)
'anarchic' is the definition.
(synonyms)
This is all the clue.
(Other definitions for lawless that I've seen before include "Anarchic, without any controls" , "insubordinate" , "Ungoverned" , "Without rules" , "Unruly - anarchic" .)
'anarchic' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for riotous that I've seen before include "Wild, uncontrolled" , "Unruly U rebellious" , "Anarchic" , "Artificial fabric" , "Involving wild behaviour" .)