Life

Circle
1 a: a ring, halo
   b: close plane curve every point of which is equal distance from a fixed point within the curve
2: the orbit or period of revolution of a celestial body

Sphere
1: the apparent surface of the heavens of which half forms the dome of the visible sky
2 a: one of the concentric and eccentric revolving spherical transparent shells in which according to ancient astronomy stars, suns, planets and moon are set
   b: a globe depicting such a sphere; broadly