Thus getting attorney a drink (4)
I believe the answer is:
soda
'a drink' is the definition.
(soda is a kind of drink)
'thus getting attorney' is the wordplay.
'thus' becomes 'so' (synonyms).
'getting' means one lot of letters go next to another.
'attorney' becomes 'D.A.' (abbreviation for District Attorney).
'so'+'da'='SODA'
(Other definitions for soda that I've seen before include "Type of bread, water or fountain" , "kind of water" , "In the US, a sweet fizzy drink" , "Mixer drink" , "Variety of pop" .)