A chairman or chairwoman, someone who presides over a meeting, board, etc.
A chief officer or administrator, especially one who can make significant decisions on their own authority.
A process that coordinates and governs the action of other processes or threads; supervisor.
The branch of government that is responsible for enforcing laws and judicial decisions, and for the day-to-day administration of the state.
Of, pertaining to, or having responsibility for the day-to-day running of an organisation, business, country, etc.
Designed or fitted for execution, or carrying into effect.
Exclusive.