Cross-country runner (7)
I believe the answer is:
harrier
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">cross-country runner</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 harrier that I've seen before include "Hound; bird of prey" , "jump jet" , "may get on your back?" , "Short-winged hawk" , "Long distance runner" .)