ball-and-socket joint

American  

[bawl-uhn-sok-it joint] / ˈbɔl ənˈsɒk ɪt ˌdʒɔɪnt /

noun

1. 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.

2. 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.

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ball-and-socket joint British  

noun

1. 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

2. 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

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ball-and-socket joint Scientific  

/ bôl′ən-sŏk′ĭt /

1. 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.

2. 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.

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Etymology

Origin of ball-and-socket joint

First recorded in 1660–70

Example Sentences

The unusual nocturnal animal has a venomous bite and an incredibly mobile nose thanks to a ball and socket joint.

From BBC • Nov. 9, 2012

Each of these tubercles was pitted in the centre, and into these the almost pointed ends of the rootlets fitted, as by a ball and socket joint.

From The Story of a Piece of Coal What It Is, Whence It Comes, and Whither It Goes by Martin, Edward A.

The ball and socket joint admits of motion in all directions.

From Physiology and Hygiene for Secondary Schools by Walters, Francis M.

They have a true ball and socket joint, and several small muscles which contract and relax with as perfect regularity and accuracy as any of the larger muscles of the body.

From A Treatise on Physiology and Hygiene For Educational Institutions and General Readers by Hutchison, Joseph Chrisman

Cotyla: the articular pan; the cup or socket of a ball and socket joint.

From Explanation of Terms Used in Entomology by Smith, John. B.