Sentry's call (4)
I believe the answer is:
halt
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">sentry's call</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 halt that I've seen before include "Pull up" , "Bring to a stop; lame" , "Stop, small station" , "limping" , "Stop; minor station" .)