regent

One who rules in place of the monarch, especially because the monarch is too young, absent, or disabled.

Any ruler.

A member of a municipal or civic body of governors, especially in certain European cities.

This perception, however, does no justice to the regents of the city of Amsterdam.

A member of governing board of a college or university; also a governor of the Smithsonian Institution in Washington, D.C.

The chief executive of a regency.

Ruling; governing; regnant.

Some other active regent principle […] which we call the soul.

Exercising vicarious authority.

the regent powers

A city in North Dakota.