regent

johtokunnan jäsen

valtionhoitaja, sijaishallitsija

hallitseva puhekieltä A ruler. (defdate)
One who rules in place of the monarch, especially because the monarch is too young, absent, or disabled. (defdate)
puhekieltä A member of a municipal or civic body of governors, especially in certain European cities. (defdate)
1999, (w), translating Geert Mak, Amsterdam: A Brief Life of the City, Vintage 2001, p. 139:

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

Some other active regent principle (..) which we call the soul.

(rfquotek)