Ban this awful drink (7)
I believe the answer is:
absinth
'drink' is the definition.
(absinth is a kind of drink)
'ban this awful' is the wordplay.
'awful' is an anagram indicator.
'ban'+'this'='banthis'
'banthis' is an anagram of 'ABSINTH'.
(Other definitions for absinth that I've seen before include "Strong liquor in baths, strangely" , "Shrubby plant" , "Potent liqueur, originally made with wormwood" , "sort of liqueur" , "Aniseed-flavoured liqueur" .)