A head rest (6)
I believe the answer is:
pillow
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">a head rest</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 pillow that I've seen before include "place to lay his head" , "Soft place for the head" , "Cushion for head" , "Sleeper's cushion" , "Bed cushion" .)