The distal bone is capable of motion around an indefinite number of axes, which have one common center.

This enables the joint to move in many directions.

An enarthrosis is a special kind of spheroidal joint in which the socket covers the sphere beyond its equator.

[1] Examples of this form of articulation are found in the hip, where the round head of the femur (ball) rests in the cup-like acetabulum (socket) of the pelvis; and in the shoulder joint, where the rounded upper extremity of the humerus (ball) rests in the cup-like glenoid fossa (socket) of the shoulder blade.

This article incorporates text in the public domain from page 287 of the 20th edition of Gray's Anatomy (1918)