Verbal dig (4)
I believe the answer is:
slur
'verbal dig' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for slur that I've seen before include "Speak indistinctly, as a drunk might" , "Innuendo" , "Speak as drunk perhaps" , "Negative comment" , "Insinuation; indistinct utterance" .)