JFK (7)
I believe the answer is:
kennedy
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">jfk</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 kennedy that I've seen before include "Nigel -, Br. violinist" , "US president, d. 1963" , "Murdered US president" , "US president assassinated in Dallas" , "Youngest US President" .)