Small drink of alcohol and a jerk gets theatrical (8)
I believe the answer is:
dramatic
'theatrical' is the definition.
(thesaurus)
'small drink of alcohol and a jerk' is the wordplay.
'small drink of alcohol' becomes 'dram' (I've seen this before).
'and' is a charade indicator (letters next to each other).
'jerk' becomes 'tic' (I've seen this before).
'dram'+'a'+'tic'='DRAMATIC'
'gets' acts as a link.
(Other definitions for dramatic that I've seen before include "spectacular" , "Relating to theatre and acting" , "might be staggering" , "Sudden and striking" , "Like theatre" .)