Short theatrical work, shortened (4)
I believe the answer is:
dram
'short' is the definition.
(both can mean a small alcoholic drink)
'theatrical work shortened' is the wordplay.
'theatrical work' becomes 'drama' (I've seen this before).
'shortened' means to remove the last letter.
'drama' with its last letter taken away is 'DRAM'.
(Other definitions for dram that I've seen before include "Small drink of scotch" , "shot" , "Small drink of spirits" , "Measure of Scotch" , "Small drink (Scots)" .)