Barrel makers (7)
I believe the answer is:
coopers
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">barrel makers</span>' is the definition.<br/ ><span class="explanation-format__explanation">('cooper' can be a synonym of 'barrel maker')</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for coopers that I've seen before include "They make barrels" , "Barrel-makers" , "Makers of barrels" .)