X-rated outside broadcast picture (7)
I believe the answer is:
obscene
'x-rated' is the definition.
(I've seen this before)
'outside broadcast picture' is the wordplay.
'outside broadcast' becomes 'ob'.
'picture' becomes 'scene' (synonyms).
'ob'+'scene'='OBSCENE'
(Other definitions for obscene that I've seen before include "Indecent, lewd" , "Repugnant; indecent" , "Bawdy" , "X-rated" , "Lewd or loathsome" .)