Jeers (4)
I believe the answer is:
boos
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">jeers</span>' is the definition.<br/ ><span class="explanation-format__explanation">(boos from a crowd)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for boos that I've seen before include "Sounds of disapproval" , "Catcalls" , "Shouts of derision" , "Shows disapproval" , "Shouts of disapproval" .)