Winged horse of Greek myth (7)
I believe the answer is:
pegasus
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">winged horse of greek myth</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for pegasus that I've seen before include "with a place in the firmament" , "group of stars" , "Winged horse - constellation" , "Northern hemisphere constellation - use gaps (anag)" , "Flier" .)