Feral American horse (7)
I believe the answer is:
mustang
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">feral american horse</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 mustang that I've seen before include "SW US wild horse" , "Wild horse of the West" , "Ford car, first produced in 1964" , "Wild or half-wild horse" , "Hardy wild horse of the American western plains" .)