We're breaking jug (4)
I believe the answer is:
ewer
'jug' is the definition.
(type of vessel)
'we're breaking' is the wordplay.
'breaking' is an anagram indicator.
'were' with letters rearranged gives 'EWER'.
(Other definitions for ewer that I've seen before include "Container" , "Jug with wide spout" , "29 [VESSEL]" , "Large water jug" , "Were (anag)" .)