Jokester (3)
I believe the answer is:
wag
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">jokester</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for wag that I've seen before include "He must be joking" , "Vibrate; jester" , "Shake" , "Oscillate - wit" , "Wave to and fro, as a dog's tail" .)