ball-and-sock·et joint (bôl′ən-sŏkĭt)
1. A synovial joint, such as the shoulder or hip joint, in which a spherical knob or knoblike part of one bone fits into a cavity or socket of another, so that some degree of rotary motion is possible in every direction. Also called enarthrosis.
2. A joint, as in a mechanical device, that permits rotary movement in all directions through the movement of a ball in a socket. Also called ball joint.
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