War-horse (5)
I believe the answer is:
steed
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">war-horse</span>' is the definition.<br/ ><span class="explanation-format__explanation">(steed is a kind of war-horse)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for steed that I've seen before include "Spirited horse" , "Literary term for horse" , "Trusty horse" , "ride" , "Swift horse" .)