Show violence towards powerful member (9)
I believe the answer is:
strongarm
'show violence towards' is the definition.
(I've seen this before)
'powerful member' is the wordplay.
'powerful' becomes 'strong' (associated in meaning).
'member' becomes 'arm' (member can mean a limb).
'strong'+'arm'='STRONGARM'
(Other definitions for strongarm that I've seen before include "Bullying" , "Show violence towards" .)