Cover (pipes) (3)
I believe the answer is:
lag
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">cover pipes</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 lag that I've seen before include "Old convict - dally - insulate" , "Protect from cold" , "person inside" , "Fall behind; insulate" , "Ex-convict" .)