Being broadcast (2,3)
I believe the answer is:
on air
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">being broadcast</span>' is the definition.<br/ ><span class="explanation-format__explanation">(on air on radio or TV)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for on air that I've seen before include "In the act of broadcasting" , "Broadcasting studio sign" , "In the process of broadcasting - floating aloft?" , "In the process of broadcasting on radio or TV" , "now showing" .)