Attempt to get a small whisky? (4)
I believe the answer is:
shot
I believe this clue is a double definition.
'attempt' is the first definition.
(shot is a kind of attempt)
'a small whisky?' is the second definition.
(as in a shot of whisky)
'to get' acts as a link.
(Other definitions for shot that I've seen before include "Fired a gun" , "Small drink of spirits" , "Small drink of liquor" , "Fired; turn" , "glass of spirits" .)