Vocation == profession. For example: students who want to learn a vocation like welding go to vocational school. Vacation: I am going on vacation == I am going on holiday. Americans tend to use the word "vacation" instead of "holiday" when talking about a trip. Sometimes I will say that I am going "on holiday" if I want to sound particularly posh or British, but it's said with a very tongue-in-cheek tone.

Vacation= holiday, and Vocation= job

thank you all.