Additional drink for engraver (6)
I believe the answer is:
chaser
This clue is a double definition.
'additional drink' is the first definition.
(alcoholic drink taken with another one)
'for engraver' is the second definition.
(I've seen this before)
(Other definitions for chaser that I've seen before include "engraver" , "Racehorse - search (anag)" , "Racing horse" , "Drink of beer after spirit" , "Huntsman" .)