Foot curve (4)
I believe the answer is:
arch
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">foot curve</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 arch that I've seen before include "Mysterious - curve" , "Wellington's, perhaps" , "Annoyingly playful" , "Vault; roguish" , "Curved aperture" .)