Drink for one lifting medal (6)
I believe the answer is:
eggnog
'drink' is the definition.
(eggnog is a kind of drink)
'for one lifting medal' is the wordplay.
'for one' becomes 'eg' (both can mean 'for example').
'lifting' says the letters should be written in reverse.
'medal' becomes 'gong' (informal term for a medal or prize).
'gong' back-to-front is 'gnog'.
'eg'+'gnog'='EGGNOG'
(Other definitions for eggnog that I've seen before include "Festive dairy beverage" , "Xmas tipple" , "Yellowish mixed alcoholic drink" , "Punch comprising cream and other farm produce" , "Christmas drink" .)