what is radius

The distance between centre and circumference of a circle is called radius.

In a circle radius is the half of its diameter.which is d=2r

a straight line from the centre to the circumference of a circle or sphere.plural form is radii.the distance from the centre of a circle to the point on the circle is called radius.

It is the distance between centre and circumference.

a straight line from the centre to the circumference of a circle or sphere

Aline which one end is on the centre and another is on the boundry of circle , that line is radius .