Fellow traveller elevated -- it's the booze (6)
I believe the answer is:
pernod
'the booze' is the definition.
(Pernod is an example)
'fellow traveller elevated' is the wordplay.
'fellow' becomes 'don' (both can mean an academic).
'traveller' becomes 'rep' (travel company worker).
'elevated' says the letters should be written backwards (in a down clue, letters go up).
'don'+'rep'='donrep'
'donrep' backwards is 'PERNOD'.
'it's' acts as a link.
(Other definitions for pernod that I've seen before include "Aniseed-flavoured aperitif" , "Aniseed-flavoured drink" , "Ponder on this liqueur" , "Drink flavoured with aniseed" , "Brand of pastis" .)