Two dears getting sozzled imbibing a drink (4,5)
I believe the answer is:
soda water
'drink' is the definition.
(I know that soda water is a type of soft drink)
'two dears getting sozzled imbibing a' is the wordplay.
'getting sozzled' indicates an anagram (sozzled can mean drunk and therefore disordered).
'imbibing' is an insertion indicator.
'two'+'dears'='twodears'
'twodears' is an anagram of 'sodawter'.
'sodawter' going around 'a' is 'SODA WATER'.
(Other definitions for soda water that I've seen before include "Fizzy drink" , "Possible splash" , "Fizzy mixer" , "Carbonated drink" , "Aerated drink" .)