Useful thing (5)
I believe the answer is:
asset
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">useful thing</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 asset that I've seen before include "good point" , "One bringing benefit" , "Boon" , "Valued item" , "Valuable thing" .)