Cheer starter (3)
I believe the answer is:
hip
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">cheer starter</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for hip that I've seen before include "Swinging" , "Slangily trendy part of body" , "Trendy bodily joint?" , "Fruit of the wild rose (3)" , "Leg joint" .)