The most common and most likely answer to this crossword clue is the 9 letter word ASCENDERS
I've seen this crossword clue in Financial Times
A
S
C
E
N
D
E
R
S
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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 ASCENDERS mean?
ASCENDERS noun- A person or thing that ascends.
- (graphology) The portion of a lowercase letter that extends above the midline.
- A mechanical device used for ascending on a rope; ascendeur.