Imbibe slowly (3)
I believe the answer is:
sip
'imbibe slowly' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for sip that I've seen before include "Smallest drink" , "Take small mouthfuls of (drink)" , "Tiny amount of drink" , "Small mouthful of liquid" , "Drink daintily" .)