Vessel heading off later (4)
I believe the answer is:
ewer
'vessel' is the definition.
(ewer is a kind of vessel)
'heading off later' is the wordplay.
'heading off' means to remove the first letter.
'later' becomes 'newer' ('new' can be similar in meaning to 'late').
'newer' with its initial letter taken off is 'EWER'.
(Other definitions for ewer that I've seen before include "Jar for water" , "Large pitcher" , "A wide-lipped jug" , "Big jug" , "Container" .)