Openly disobey the loud thug (5)
I believe the answer is:
flout
'openly disobey' is the definition.
(I've seen this in another clue)
'loud thug' is the wordplay.
'loud' becomes 'f' (short for forte - 'loud' in music).
'thug' becomes 'lout'.
'f'+'lout'='FLOUT'
'the' acts as a link.
(Other definitions for flout that I've seen before include "Show contempt for, defy" , "Show blatant disregard for" , "Treat with disdain" , "Disobey openly and scornfully" , "Mock" .)