Review on thug's weapon (7)
I believe the answer is:
shotgun
'weapon' is the definition.
(shotgun is a kind of weapon)
'review on thug's' is the wordplay.
'review' is an anagram indicator.
'on'+'thugs'='onthugs'
'onthugs' is an anagram of 'SHOTGUN'.
(Other definitions for shotgun that I've seen before include "arm" , "Noughts (anag) - type of wedding" , "No thugs (anag) - weapon" , "Smooth-bore weapon" , "Hunting firearm" .)