Mislaid (4)
I believe the answer is:
lost
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">mislaid</span>' is the definition.<br/ ><span class="explanation-format__explanation">('lose' can be a synonym of 'mislay')</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for lost that I've seen before include "confused" , "Baffled" , "at sea" , "Forgotten; misplaced" , "Mislaid or was defeated" .)