In the arms of Morpheus (6)
I believe the answer is:
asleep
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">in the arms of morpheus</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 asleep that I've seen before include "Inattentive; numbed" , "Conked out" , "In the Land of Nod" , "See, pal strangely is not awake" , "Dormant; inattentive" .)