Left state in old vessel (5)
I believe the answer is:
laver
'old vessel' is the definition.
(historic term for a type of basin)
'left state' is the wordplay.
'left' becomes 'l' (common abbreviation).
'state' becomes 'aver' (I've seen this before**).
'l'+'aver'='LAVER'
'in' is the link.
(Other definitions for laver that I've seen before include "Edible seaweed" , "Rod - - (tennis)" , "Tennis player" , "Wimbledon champ" .)