Sky broadcast (3)
I believe the answer is:
air
I believe this clue is a double definition.
'sky' is the first definition.
(I've seen this before)
'broadcast' is the second definition.
(to air on TV)
(Other definitions for air that I've seen before include "Vent; atmosphere" , "Feel" , "Broadcast; tune" , "A tune or attitude" , "Expose" .)