Metier (noun)

A trade, profession, or field of work in which a person has been trained or has developed expertise.

Origin:

From the french "métier" meaning "trade or profession".

Examples:

1. He has a real talent for acting and it's his metier.
2. She has found her metier as a teacher.
3. The artist has been working in his metier for over 30 years.
4. Being a lawyer is not his metier, he would prefer to be an artist.
5. He has a great talent for music, it's his true metier.