Willingly enjoy drink of spirits (4,1,4)
I believe the answer is:
like a shot
'willingly' is the definition.
(to do something like a shot is to do it willingly)
'enjoy drink of spirits' is the wordplay.
'enjoy' becomes 'like' (like can mean to appreciate or enjoy something).
'drink of spirits' becomes 'a shot' (an alcoholic shot).
'like'+'ashot'='LIKE A SHOT'
(Other definitions for like a shot that I've seen before include "straightaway?" , "show partiality for spirits" , "What serious drinkers do" , "At once, willingly" , "warm quickly" .)