Wacko
I believe the answer is:
nuts
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">wacko</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 nuts that I've seen before include "out to lunch" , "Hard-shelled fruit" , "Mad - hard fruits" , "Edible seeds with hard shells" , "Stun (anag.)" .)