He made me bugging so much with that..."trimestre" is 3 months in french. Anyway it was better to change and use "quarter" in this context.
Trimester literally means 3 months in Latin, so yeah, a trimester is a quarter of a year. But you have only 3 trimesters at school because the 4th one is the school holidays, taken together. Hence why there's only 3 trimesters for most people who talk about them.
The Nintendo eShop rating Thread: http://gamrconnect.vgchartz.com/thread.php?id=237454