Violent hoodlum and thug regularly a blusterer (9)
I believe the answer is:
loudmouth
'a blusterer' is the definition.
(I know that blusterer can be written as loudmouth)
'violent hoodlum and thug regularly' is the wordplay.
'violent' indicates an anagram.
'and' is a charade indicator (letters next to each other).
'regularly' indicates alternate letters (regularly take one letter, leave next etc.).
The alternating letters of 'thug' are 'tu'.
'hoodlum' after 'tu' is 'tuhoodlum'.
'tuhoodlum' with letters rearranged gives 'LOUDMOUTH'.
(Other definitions for loudmouth that I've seen before include "Pistol, for example" , "noisy type" , "boastful type?" , "Blowhard" , "One who causes trouble by speaking indiscreetly" .)