- Breakfast is petit déjeuner, i.e. little déjeuner
- Lunch is déjeuner
- Dinner is dîner
And in the Canadian province of Quebec,
- Breakfast is déjeuner
- Lunch is dîner
- Dinner is souper
So why is the vocabulary used in France and in Quebec different for the meals of the day?
There was actually a period in the past when both regions used déjeuner for breakfast, dîner for lunch, and souper for dinner, but after the French Revolution, i.e. after the British gained control of Quebec as a result of the Seven Years War, the French started to have breakfast later. So they began to call the midday meal déjeuner and the meal before noon le petit déjeuner (i.e. the little déjeuner).
Therefore, it is the Quebecers who have kept the original sense of the words déjeuner, dîner, and souper.