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

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

In the ball and socket joint the ball-shaped end of one bone fits into a cup-shaped cavity in another bone, called the socket.

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

This articulation is a perfect specimen of the ball and socket joint.

From A Treatise on Anatomy, Physiology, and Hygiene (Revised Edition) by Cutter, Calvin

Trochalopoda: Heteroptera in which the posterior coxae are nearly globose and the articulation is a ball and socket joint: see pagiopoda.

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