The most common and most likely answer to this crossword clue is the 13 letter word CHOREOGRAPHER
I've seen this crossword clue in Financial Times
C
H
O
R
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G
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A
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More clues leading to the result CHOREOGRAPHER
- Creator of steps in routine task old mathematical plotter follows
- Professional person who may develop a routine
- Dance creator in job with reverse of average work ahead of her
- Hog! 9 cars he wrecked, avoiding small person leading us a merry dance!
- One who indicates what steps must be followed
- He makes routine arrangements for performers
- I arrange steps?
Buddy explains!
The straight part
We know that "Professional person who may develop a routine" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case professional person who may develop a routine = choreographer.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 CHOREOGRAPHER mean?
CHOREOGRAPHER noun- A person who choreographs.