Hich term refers to a form of collective social behavior that persists over a long period and gradually finds place as a tradition in society?

A form of collective social behavior that persists over a long period and gradually finds place as a tradition is called a custom. Examples:

Drinking a glass of wine with each meal--French custom (although that might changing due to economic woe and other variables)

Saying a prayer before each meal--Latin American custom (although it's a custom in other places too, and not every Latin American does this)