Shakespeare, perhaps, is forbidden on the radio (4)
I believe the answer is:
bard
'shakespeare perhaps' is the definition.
'forbidden on the radio' is the wordplay.
'forbidden' becomes 'barred' (barring is a kind of forbidding).
'on the radio' shows a homophone (sound like).
'barred' sounds like 'BARD'.
'is' acts as a link.
(Other definitions for bard that I've seen before include "Epic poet" , "Poet; sounds like forbidden" , "Ancient poet" , "A drab sort of old poet" , "Gray, perhaps" .)