Radius
The distance between the focal point and the center of a circle is called the radius. It is a fixed distance that remains constant for a given circle.
it is called the "center"
The distance a piston travels within the cylinder is called the stroke. It is the distance between the top dead center (TDC) and the bottom dead center (BDC) positions of the piston.
It is called the radius. The full distance is called the diameter.
The radius is from the centre to the rim of a circle.
The radius is the distance between the center of a circle and a point on the circle
The distance from the center of a mirror to the focal point is called the focal length.
The distance from the center of a mirror to the focal point is called the focal length.
The distance from one side of a circle to the other going through the center is called the Diameter, the distance from any side to the center (half the diameter) is called the radius.
All lathes could be considered "centre lathes." You turn "between centers." There's also a tool called a "machining center," but those are for computerized milling, normally of metal.
The distance between the center and the edge of a circle is called the radius. It is constant for a given circle and is measured in any linear unit, such as meters or inches. The radius is half the length of the circle's diameter, which spans from one edge of the circle to the opposite edge through the center.
Atomic center is the center of the atom, also called as Nucleus. Atomic Radius is the distance between the center of the nucleus and outermost shell of the atom. It is nearly about 1.2 * 10-10 m.