Low point (5)
I believe the answer is:
nadir
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">low point</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for nadir that I've seen before include "Rock bottom" , "extremely low position" , "Drain into the lowest point (5)" , "lowest of the low" , "Given lowest place" .)