Cutter's heading off vessel (4)
I believe the answer is:
ewer
'vessel' is the definition.
(ewer is a type of jug)
'cutter's heading off' is the wordplay.
'cutter' becomes 'hewer' (I've seen this before).
'heading off' means to remove the first letter.
'hewer' with its first letter taken away is 'EWER'.
(Other definitions for ewer that I've seen before include "Vessel for pouring" , "Sort of jug" , "A wide-lipped jug" , "Water jug with wide mouth" , "Large water-jug" .)