Act inferior and unruly (7)
I believe the answer is:
lawless
'unruly' is the definition.
(thesaurus)
'act inferior' is the wordplay.
'act' becomes 'law' (law is a kind of act**).
'inferior' becomes 'less' ('less' can be similar in meaning to 'inferior').
'law'+'less'='LAWLESS'
'and' is the link.
(Other definitions for lawless that I've seen before include "Ungoverned" , "Slew Sal for being criminal" , "insubordinate" , "Unruly - anarchic" , "Without rules" .)