Delinquent split weak barrel (10)
I believe the answer is:
lawbreaker
'delinquent' is the definition.
(I've seen this before)
'split weak barrel' is the wordplay.
'split' indicates an anagram (letters split up and reassembled).
'weak'+'barrel'='weakbarrel'
'weakbarrel' anagrammed gives 'LAWBREAKER'.
(Other definitions for lawbreaker that I've seen before include "Perpetrator of crime" , "Delinquent" , "Criminal" , "Villain" .)