The most common and most likely answer to this crossword clue is the 13 letter word CHRYSANTHEMUM
I've seen this crossword clue in Independent
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More clues leading to the result CHRYSANTHEMUM
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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 CHRYSANTHEMUM mean?
CHRYSANTHEMUM noun- Any of many flowering perennial plants, of the genus Chrysanthemum, native to China, that have showy radiate heads.