Work period (5)
I believe the answer is:
shift
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">work period</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for shift that I've seen before include "Time when group of people are working" , "underskirt" , "Move quickly; dress" , "Change position" , "Team of workers" .)