Short skirt (4)
I believe the answer is:
mini
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">short skirt</span>' is the definition.<br/ ><span class="explanation-format__explanation">(mini skirt)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for mini that I've seen before include "(Car etc) of small size" , "Car designed by Issigonis" , "Iconic economy car (introduced in 1959)" , "type of garment" , "vehicle" .)