Excluded by group on the radio (6)
I believe the answer is:
banned
'excluded' is the definition.
(thesaurus)
'group on the radio' is the wordplay.
'group' becomes 'band' (band is a kind of group).
'on the radio' indicates a 'sounds like' (homophone) clue.
'band' sounds like 'BANNED'.
'by' is the link.
(Other definitions for banned that I've seen before include "Barred" , "Forbidden by law" , "Outlawed" , "Prohibited by censor" , "Taboo" .)