Oversized jug (4)
I believe the answer is:
ewer
'oversized jug' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for ewer that I've seen before include "Water jug with wide mouth" , "A wide-lipped jug" , "Open vessel with handle and spout" , "Large pitcher" , "Large water-jug" .)