Drink beer, drinking round (5)
I believe the answer is:
pinot
'drink' is the definition.
(I've seen this before)
'beer drinking round' is the wordplay.
'beer' becomes 'pint' (beer is typically served by the pint).
'drinking' means one lot of letters goes inside another (inserted letters are consumed or drunk).
'round' becomes 'o' (o is a circular letter).
'pint' going around 'o' is 'PINOT'.
(Other definitions for pinot that I've seen before include "Red or white ingredient" , "Variety of wine grape" , "Wine-making grape" , "Kind of wine grape" , "drink" .)