The most common and most likely answer to this crossword clue is the 9 letter word ANNOTATOR
A
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More clues leading to the result ANNOTATOR
- Literary editor, one turning up I dispensed with
- Interpreter can’t head off before returning register
- She’ll explain rule on non-standard double contributions by NATO
- He makes explanatory notes on “Art at Noon” perhaps
- He interprets article by turning over without interest
- Writer of comments from Wigan, not a Tory
Buddy explains!

The straight part
We know that "Writer of comments" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case writer of comments = annotator.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.