championship
The French word 'championnat' is used in the same context as the English word 'championship'. It refers to a competition or series of competitions to determine the best in a particular field or activity. For example, 'Le championnat du monde de football' means 'The World Football Championship'.
He won the championship last year.
This sentence is explaining that a specific person (Il) won (a gagné) a championship (le championnat) in the previous year (l'année dernière).
The championship starts next week.
This sentence is talking about a specific championship (Le championnat) that is starting (commence) the following week (la semaine prochaine).
My favorite team is at the top of the championship.
This sentence is stating that the speaker's favorite team (Mon équipe préférée) is leading or at the top (est en tête) of the championship (du championnat).