Ecstasy's opposite (5)
I believe the answer is:
agony
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">ecstasy's opposite</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 agony that I've seen before include "Distress" , "Severe pain, mental or physical" , "Excruciating pain" , "Intense pain" , "Extreme suffering - kind of aunt" .)