The most common and most likely answer to this crossword clue is the 7 letter word TRADUCE
I've seen this crossword clue in The Guardian
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More clues leading to the result TRADUCE
- Speak badly of drug, taken regularly in tiny amount
- Slander a duke during armistice
- Malign notice interrupts attempt to stop war
- Defame jazz function in speech
- Speak badly of a duke breaking ceasefire
- Deal framing upstanding copper is malign
- Malign exchange about University College
- Speak badly of business involving University College
- Bad-mouth picture put up by Mussolini
- Malign piece of publicity breaking ceasefire
Buddy explains!

The straight part
We know that "Vilify" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case vilify = traduce.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does TRADUCE mean?
TRADUCE verb- To malign a person or entity by making malicious and false or defamatory statements.
- To pass on (to one's children, future generations etc.); to transmit.
- To pass into another form of expression; to rephrase, to translate.