'Some alcohol!' I belligerently slur (5)
I believe the answer is:
libel
'slur' is the definition.
(thesaurus)
'some alcohol i belligerently' is the wordplay.
'some' indicates the answer is hidden within the clue (some of the parts of the word are used).
'LIBEL' is hidden within 'alcohol i belligerently'.
(Other definitions for libel that I've seen before include "Calumny" , "A published false statement that damages someone" , "Defame in writing" , "Defamatory publication" , "Actionable words" .)