Offend (6)
'offend' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for miff that I've seen before include "Annoy - offend" , "Take offence" , "Put in a bad mood" , "Wind up" , "minor quarrel" .)
'offend' is the definition.
(insulting is a kind of offending)
This is the entire clue.
(Other definitions for insult that I've seen before include "Abusive remark" , "Cause offence to" , "Abuse (someone)" , "Treat disrespectfully" , "Treat with abuse" .)