A set of drinks on all sides (6)
I believe the answer is:
around
'on all sides' is the definition.
(I've seen this before)
'a set of drinks' is the wordplay.
'set of drinks' becomes 'round' (as in a round of drinks ordered at a bar).
'a'+'round'='AROUND'
(Other definitions for around that I've seen before include "In the area of" , "On all sides or near" , "More or less" , "Somewhere in the vicinity" , "Here and there, sounds circular" .)