Sly slur (8)
I believe the answer is:
innuendo
'sly slur' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for innuendo that I've seen before include "Suggestive remark" , "Indirect reference to something rude" , "Indirect remark" , "Smutty insinuation" , "Indirect or subtle reference" .)