Keg (3)
(Other definitions for vat that I've seen before include "Large tank or vessel" , "Large barrel" , "Large container for liquid" , "Large vessel for storing liquids and a large tax" , "Large tank; purchase tax" .)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">keg</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for barrel that I've seen before include "Round wooden cask made by cooper" , "''Roll out the ..., let's have a ... of fun'' (WWII song)" , "Beer measure; gun part" , "Tun" , "Revolving drum" .)