The most common and most likely answer to this crossword clue is the 9 letter word PROUSTIAN
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More clues leading to the result PROUSTIAN
- Put on airs ridiculously, like a French author
- French writer’s work in our past
- Hack put on airs as lover of French writing
- Marcel style? Joanna has nothing trimmed, about to create a stir
- Like a great stylist Puritans love madly
- Puritan so outraged about French writer
- Like a French author favouring bombast? Not the first
Buddy explains!

The straight part
We know that "Marcel style" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case marcel style = proustian.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.