Water server (4)
I believe the answer is:
ewer
'water server' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for ewer that I've seen before include "A type of jug" , "Water-jar" , "Large, wide-mouthed jug" , "Large pitcher" , "A wide-mouthed water-jug" .)