Arrears of work (7)
I believe the answer is:
backlog
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">arrears of work</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 backlog that I've seen before include "pile needing attention?" , "Arrear of wooden kind?" , "Build-up of work still to be dealt with" , "Accumulation (of work) to be dealt with" , "Go black with arrears of work" .)