Horrify, dismay (5)
I believe the answer is:
appal
<span class="explanation-format__ClueExplanation">This clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">horrify</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(I know that horrify can be written as appal)</span><br/ ><br/ >'<span class="explanation-format__original">dismay</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(I know that dismay can be written as appal)</span><br/ ><br/ ></span>
(Other definitions for appal that I've seen before include "Outrage" , "Scandalise" , "Greatly horrify" , "Greatly dismay" , "To shock, dismay" .)