Sudden fright (5)

<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">sudden fright</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for start that I've seen before include "Move quickly < when surprised" , "Onset" , "get under way" , "Commencement" , "Jump suddenly" .)
(Other definitions for alarm that I've seen before include "Put the wind up" , "Unnerve" , "Warning bell" , "Sudden apprehension and fear" , "Arouse to a sense of danger" .)