The most common and most likely answer to this crossword clue is the 9 letter word VEXATIOUS
I've seen this crossword clue in Independent
V
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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 VEXATIOUS mean?
VEXATIOUS adjective- Causing vexation or annoyance; teasing; troublesome.
- Full of trouble or disquiet
- (of an action) Commenced for the purpose of giving trouble, without due cause.
- (of a party or entity) In the habit of starting vexatious litigation and therefore liable to have restraints placed on one's ability to access the courts.