Gormless (13)
I believe the answer is:
unintelligent
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">gormless</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for unintelligent that I've seen before include "Stupid" , "Gormless" , "Lacking wit" , "Foolish" .)