Cease to participate (4,3)
I believe the answer is:
drop out
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">cease to participate</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for drop out that I've seen before include "rugby manoeuvre" , "leave society?" , "Kick" , "twenty-two" , "One who withdraws" .)