Period of time in prison (7)
I believe the answer is:
stretch
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">period of time in prison</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 stretch that I've seen before include "Extend, elongate" , "that one may do to a point" , "Period inside" , "Lengthen - time in jail" , "Period of time in prison" .)