The most common and most likely answer to this crossword clue is the 8 letter word FUMITORY
I've seen this crossword clue in Financial Times
F
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M
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T
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Y
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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 FUMITORY mean?
FUMITORY noun- A plant of the taxonomic genus Fumaria, which are annual herbaceous flowering plants in the family Papaveraceae, native to temperate Europe and Asia.