What is french nose?

It's not clear what you mean by "French nose."

If you are referring to the physical features of a French person's nose, it is not possible to make such generalizations. French people, like people from any other country, come in all shapes and sizes, and their noses can vary widely.

If you are asking about the term "French nose" in the context of wine tasting, it refers to the ability to identify the aromas of a wine. The French have been known for their wine expertise and are often credited with developing the language and vocabulary used to describe the smells and tastes of wine. A "French nose" would be someone who had a highly developed sense of smell and taste and could identify the subtle nuances of a wine.