The most common and most likely answer to this crossword clue is the 9 letter word CULMINATE
I've seen this crossword clue in Independent
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More clues leading to the result CULMINATE
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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 CULMINATE mean?
CULMINATE verb- Of a heavenly body, to be at the highest point, reach its greatest altitude.
- To reach the (physical) summit, highest point, peak etc.
- To reach a climax; to come to the decisive point (especially as an end or conclusion).
- To finalize, bring to a conclusion, form the climax of.
- Relating to the culmen