A component of a system that executes or runs something.
Someone appointed by a testator to administer a will; an administrator.
A person who carries out some task.
The source of a river, information, goods, etc.
The proximal end of attachment of a muscle to a bone that will not be moved by the action of that muscle.
An arbitrary point on Earth's surface, chosen as the zero for a system of coordinates.
The beginning of something.
Ancestry.
The point at which the axes of a coordinate system intersect.