Complete collection (3)
I believe the answer is:
set
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">complete collection</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 set that I've seen before include "Place - become rigid - adjust - group of tennis games - fixed - clique - fall beneath the horizon" , "Mount (gem); scenery" , "Fix; lay" , "Become stiff like jelly" , "Determined or congealed" .)