Final demand (9)
I believe the answer is:
ultimatum
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">final demand</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 ultimatum that I've seen before include "Uncompromising demand" , "Final (peremptory) demand" , "Final proposition or demand" , "Final statement of actions required of another" , "Final offer" .)