The most common and most likely answer to this crossword clue is the 9 letter word GREENMAIL
I've seen this crossword clue in Independent
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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 GREENMAIL mean?
GREENMAIL noun- Profiting from an attempted hostile takeover by forcing the target company to buy back the hostile bidder's shares at an inflated price.
- To profit from an attempted hostile takeover by forcing the target company to buy back the hostile bidder's shares at an inflated price.