It's about a foot (4)
I believe the answer is:
shoe
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">it's about a foot</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 shoe that I've seen before include "Trainer, for instance" , "What one needs for a horse" , "Plate nailed to underside of horse's hoof" , "Case from which playing cards are delt one at a time" , "Oxford, say" .)