Corporation at airing, soon being broadcast (12)
I believe the answer is:
organisation
'corporation' is the definition.
(corporation is a type of organisation)
'at airing soon being broadcast' is the wordplay.
'being broadcast' indicates an anagram.
'at'+'airing'+'soon'='atairingsoon'
'atairingsoon' is an anagram of 'ORGANISATION'.
(Other definitions for organisation that I've seen before include "Systematic approach to tasks" , "System" , "Running" , "concern" .)