Last in pub always gets older drinks (9)
I believe the answer is:
beverages
'drinks' is the definition.
('beverage' can be a synonym of 'drink')
'last in pub always gets older' is the wordplay.
'last in' suggests the final letters.
'always' becomes 'ever' (synonyms).
'gets older' becomes 'ages' ('age' can be a synonym of 'get older').
The final letter of 'pub' is 'b'.
'b'+'ever'+'ages'='BEVERAGES'
(Other definitions for beverages that I've seen before include "Vegas beer (anag) - beer etc" , "Drinks" .)