Party with odd bits of wine to drink (4)
I believe the answer is:
down
'drink' is the definition.
(downing is a kind of drinking)
'party with odd bits of wine' is the wordplay.
'party' becomes 'do' (do is a kind of party).
'with' says to put letters next to each other.
'odd bits of' indicates alternate letters.
The alternate letters of 'wine' are 'wn'.
'do'+'wn'='DOWN'
'to' is the link.
(Other definitions for down that I've seen before include "Depressed - feathers" , "Depressed - Irish county" , "Pillow filler - dejected" , "Soft feathers (like this clue)" , "Soft fine feathers" .)