Frightening creature (7)
I believe the answer is:
monster
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">frightening creature</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for monster that I've seen before include "something large and ugly" , "Large or misshapen creature" , "Inhuman person" , "Huge ugly creature" , "Fabulous beast" .)