Adjustable spanner (6)
I believe the answer is:
wrench
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">adjustable spanner</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 wrench that I've seen before include "Violent twist - (adjustable) spanner" , "Tear away" , "Sprain - difficult parting" , "Yank" , "Kind of spanner or severe twist" .)