A more thorough explanation:

Capitalis custos is a Latin term that means "chief guardian." In history, it referred to:

1. A chief warden or magistrate.
2. Loosely, a mayor.

For example, in ancient Rome, the capitalis custos was responsible for maintaining law and order in the city. They were in charge of the city's prisons and had the power to impose punishments on criminals.

In modern times, the term can be used to refer to the mayor of a city or town. The mayor is often seen as the chief guardian of the city, responsible for ensuring the safety and well-being of its citizens.