Company business comes before a drink (5)
I believe the answer is:
cocoa
'drink' is the definition.
(cocoa is a kind of drink)
'company business comes before a' is the wordplay.
'company' becomes 'co' (abbreviation).
'business' becomes 'co' (short for company).
'comes before' says to put letters next to each other.
'co'+'co'+'a'='COCOA'
(Other definitions for cocoa that I've seen before include "Hot chocolate drink" , "Late-night drink" , "Warming bedtime drink" , "Kind of chocolate drink" , "Popular chocolate drink" .)