Disparaging, abusive (10)
I believe the answer is:
scurrilous
I believe this clue is a double definition.
'disparaging' is the first definition.
(thesaurus)
'abusive' is the second definition.
(I know that abusive can be written as scurrilous)
(Other definitions for scurrilous that I've seen before include "Obscenely slanderous" , "Scandalously damaging" , "Humorously insulting" , "Unjustifiably defamatory" , "Grossly insulting" .)