Confine within bounds (5)
I believe the answer is:
limit
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">confine within bounds</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for limit that I've seen before include "Curb" , "Bound, restriction" , "Put restriction on" , "Hem in" , "speed restriction applied" .)