High-flying songbird (7)
I believe the answer is:
skylark
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">high-flying songbird</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for skylark that I've seen before include "Indulge in horseplay" , "Shelley's blithe Spirit" , "subject of 11 [ODE]" , "Common songbird" , "Flyer" .)