Time of great danger (6)
I believe the answer is:
crisis
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">time of great danger</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 crisis that I've seen before include "Turning point in disease" , "Decisive time, turning point" , "Crucial or decisive moment" , "Climax or turning point as in fever" , "Desperate situation" .)