Small drink before a show (5)
I believe the answer is:
drama
'show' is the definition.
(thesaurus)
'small drink before a' is the wordplay.
'small drink' becomes 'dram' (I've seen this before).
'before' says to put letters next to each other.
'dram'+'a'='DRAMA'
(Other definitions for drama that I've seen before include "Hamlet, say" , "shared interest of 6 & 12 [VERDI & SHAKESPEARE]" , "theatre production" , "Emotional situation" , "Play - big emotional scene" .)