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ball-and-socket joint

[bawl-uh n sok-it]

noun

Also called enarthrosis. Anatomy, Zoology. a joint in which the rounded end of one bone fits into a cuplike end of the other bone, allowing for relatively free rotary motion, as at the hip or shoulder.
Also called ball joint. a similar joint between rods, links, pipes, etc., consisting of a ball-like termination on one part held within a concave, spherical socket on the other.

Origin of ball-and-socket joint

First recorded in 1660–70
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for ball-and-socket joint

ball-and-socket joint

ball joint

noun

a coupling between two rods, tubes, etc, that consists of a spherical part fitting into a spherical socket, allowing free movement within a specific conical volume
Also called: multiaxial joint anatomy a bony joint, such as the hip joint, in which a rounded head fits into a rounded cavity, allowing a wide range of movement
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
ball-and-socket joint in Medicine

ball-and-socket joint

n.

A multiaxial joint in which a sphere on the head of one bone fits into a rounded cavity in the other bone, as in the hip joint.cotyloid joint enarthrosis
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
ball-and-socket joint in Science

ball-and-socket joint

[bôl′ən-sŏk′ĭt]

A 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.
A mechanical device consisting of a spherical knob at the end of a shaft that fits securely into a socket. Ball-and-socket joints are used to connect parts of a machine that require rotary movement in nearly all directions. Ball-and-socket joints allow the front wheels of a car to be turned by the steering mechanism.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.