Unable to keep still (7)
I believe the answer is:
restive
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">unable to keep still</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 restive that I've seen before include "Unsettled" , "Fidgety, uneasy" , "Unable to keep still" , "Impatient of authority" , "Impatient - jumpy" .)