This is the 563rd most frequent French word.
célèbre
Famous.
Here, 'célèbre' describes the uncle as being well-known within his profession or domain.
Mon oncle est un chef célèbre qui a écrit plusieurs livres de cuisine.
My uncle is a famous chef who has written several cookbooks.
In this sentence, 'célèbre' qualifies the painting, referring to its global recognition and fame.
Le tableau de Mona Lisa est une œuvre très célèbre au Louvre.
The Mona Lisa painting is a very famous artwork at the Louvre.
The word 'célèbre' is used as an adjective here to describe the city of Paris being renowned or widely known.