Insulting remark
I believe the answer is:
slur
'insulting remark' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for slur that I've seen before include "Innuendo" , "Speak disparagingly of - speak indistinctly" , "Disparagement" , "Slight - mark on music" , "Disparage" .)