This is the 8386th most frequent French word.
zénith
The highest point in the sky reached by a celestial body; figuratively, the peak or pinnacle.
Here, 'zénith' is used in its astronomical sense, referring to the highest point in the sky reached by the sun.
Le soleil atteint son zénith à midi.
The sun reaches its zenith at noon.
In this context, 'zénith' metaphorically represents the peak or culmination point of someone's career.
Son succès était au zénith de sa carrière.
His success was at the zenith of his career.
Here, 'Zénith' is used as a proper noun to indicate a specific venue for performances in Paris.