An abstract sphere of infinite radius which serves as the imaginary backdrop for celestial objects, and of which the visible sky is one hemisphere.
the figure of the universe as an imaginary sphere whose center is the Earth
A spherical physical object; a globe or ball.
The region in which something or someone is active; one's province, domain.
A regular three-dimensional object in which every cross-section is a circle; the figure described by the revolution of a circle about its diameter .
The set of all points in three-dimensional Euclidean space (or n-dimensional space, in topology) that are a fixed distance from a fixed point .
Any of the concentric hollow transparent globes formerly believed to rotate around the Earth, and which carried the heavenly bodies; there were originally believed to be eight, and later nine and ten; friction between them was thought to cause a harmonious sound (the music of the spheres).
The extension of a general conception, or the totality of the individuals or species to which it may be applied.
An area of activity for a planet; or by extension, an area of influence for a god, hero etc.
To place in a sphere, or among the spheres; to ensphere.
To make round or spherical; to perfect.