Decease (5)
I believe the answer is:
death
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">decease</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I know that decease can be written as death)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for death that I've seen before include ""The last enemy"" , "Hated (anag) - curtains (informal)" , "Extinction" , "Hated (anag) -- expiry" , "End of life" .)