Panorama is a TV broadcast (5)
I believe the answer is:
vista
'panorama' is the definition.
('vista' can be a synonym of 'panorama')
'is a tv broadcast' is the wordplay.
'broadcast' indicates anagramming the letters.
'is'+'a'+'tv'='isatv'
'isatv' anagrammed gives 'VISTA'.
(Other definitions for vista that I've seen before include "Panoramic scene" , "Prospect, view" , "Distant view" , "One gives a long look" , "Panoramic view" .)