Censored group on the radio (6)
I believe the answer is:
banned
'censored' is the definition.
('ban' can be a synonym of 'censor')
'group on the radio' is the wordplay.
'group' becomes 'band' (band is a kind of group).
'on the radio' shows a homophone (sound like).
'band' is a homophone of 'BANNED'.
(Other definitions for banned that I've seen before include "Prohibited officially" , "Outlawed" , "Prohibited by censor" , "Censored" , "expelled" .)