The most common and most likely answer to this crossword clue is the 12 letter word MADEMOISELLE
I've seen this crossword clue in Financial Times
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More clues leading to the result MADEMOISELLE
- Miss? Nice one, perhaps
- Produced German wine entertaining one unmarried French girl
- French girl produced wine around island
- Young lady produced wine, I gathered
- Nice girl caused me to tour French department lakes
- Did fashion magazine covers cut rather wet French title?
- Nice lady required me to keep nothing I trade in
- Young lady compelled doctor, single, to peddle drug
- Parisian girl produced wine, one bottled
- Nice miss using successful wine I imported
Buddy explains!

The straight part
We know that "Parisian girl" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case parisian girl = mademoiselle.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 MADEMOISELLE mean?
MADEMOISELLE noun- Courtesy title for an unmarried woman in France or a French-speaking country.
- (jocular or affected) A young woman or girl, especially one who is French or French-speaking.