Mock or jeer (5)
I believe the answer is:
taunt
<span class="explanation-format__ClueExplanation">I believe this is a double definition.<br/ ><br/ >'<span class="explanation-format__original">mock</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(I know that taunt is a type of mock)</span><br/ ><br/ >'<span class="explanation-format__original">jeer</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ ></span>
(Other definitions for taunt that I've seen before include "Jeering remark" , "Make fun of" , "Twit" , "Rag, goad" , "Mock, jeer" .)