Drink one for each sign of approval (6)
I believe the answer is:
pernod
'drink' is the definition.
(Pernod is an example)
'one for each sign of approval' is the wordplay.
'one for each' becomes 'per' (per person).
'sign of approval' becomes 'nod' (I've seen this before).
'per'+'nod'='PERNOD'
(Other definitions for pernod that I've seen before include "Ponder on this liqueur" , "Ponder on anis drink" , "French aperitif" , "Aniseed-flavoured aperitif" , "A liqueur flavoured with anise" .)