hinge joint

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A joint, such as the elbow, in which a convex part of one bone fits into a concave part of another, allowing motion in only one plane.

Any joint which permits action similar to a hinge and in which there is no appreciable separation of adjacent members.

A synovial joint that permits motions, such as extension and flexion, along a single axis only (e.g. the interphalangeal joints of the fingers, and the ulnahumeral joint of the elbow).

A uniaxial joint in which a broad, transversely cylindrical convexity on one bone fits into a corresponding concavity on the other, allowing motion in one plane only, as in the elbow. Also called ginglymoid joint.

The noun has 2 meanings:

Meaning #1: a freely moving joint in which the bones are so articulated as to allow extensive movement in one plane
  Synonyms: ginglymus, ginglymoid joint

Meaning #2: a joint allowing movement in one plane only
  Synonym: knuckle joint