Tool for nails (6)
I believe the answer is:
hammer
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">tool for nails</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 hammer that I've seen before include "Tool with heavy metal head" , "Drive nails" , "Auctioneer's mallet" , "Weaken, damage" , "It's applied to a nail" .)