Winged walker (3)
I believe the answer is:
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">winged walker</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for emu that I've seen before include "Aussie bird" , "Fast runner in Oz" , "Physics unit" , "Extinct bird" , "Big bird" .)