Horse-soldiers (7)
I believe the answer is:
cavalry
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">horse-soldiers</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 cavalry that I've seen before include "Soldiers on horseback" , "Horse soldiers" , "Military unit" , "Mounted troops" , "Horse troops" .)