Polish drinking half of beer in booze joint (7)
I believe the answer is:
shebeen
'booze joint' is the definition.
(term for a disreputable drinking establishment)
'polish drinking half of beer' is the wordplay.
'polish' becomes 'sheen' (I've seen this in another clue).
'drinking' is an insertion indicator.
'half of' means to take half the letters.
'beer' halved is 'be'.
'sheen' placed around 'be' is 'SHEBEEN'.
'in' acts as a link.
(Other definitions for shebeen that I've seen before include "Unlicensed drinking establishment" , "Illegal liquor shop" , "dive" , "still here?" , "Illicit liquor-shop" .)