Brewery tank (3)
I believe the answer is:
vat
'brewery tank' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for vat that I've seen before include "subject of 17, 8 [CHANCELLORS STATEMENT]" , "Large tank for liquids, or kind of tax" , "Large barrel" , "Large vessel for storing liquids and a large tax" , "Tank for holding liquids" .)