Female equine (4)
I believe the answer is:
mare
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">female equine</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for mare that I've seen before include "Female quadruped" , "Adult female zebra" , "Female equine animal" , "A night-time strangler" , "For classicists, sea" .)