(A) hoot – or yell (6)
I believe the answer is:
scream
<span class="explanation-format__ClueExplanation">I believe this is a double definition.<br/ ><br/ >'<span class="explanation-format__original">a hoot</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(both can mean a good time)</span><br/ ><br/ >'<span class="explanation-format__original">yell</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(I know that scream is a type of yell)</span><br/ ><br/ ></span>
(Other definitions for scream that I've seen before include "Holler" , "A shrill cry of fright" , "Hilarious character" , "Riot" , "noise?" .)