What is synovial fluid?

The joint fluid is called the synovial fluid. Gray's Anatomy (1918) describes it as a viscous, egg-white-like fluid.

What it is

  • A viscous, egg-white-like fluid.
  • Produced by the synovial membrane lining a joint capsule.
  • Lubricates the joint and nourishes the cartilage.

Where it is

  • Fills the cavity of every synovial joint.
  • Held in place by the fibrous capsule.
  • A very thin film in a healthy joint.

Source:

Last verified: 2026-07-18

  • Best Anatomy Answers is an educational reference about human anatomy. It is not medical advice — for any health concern, talk to a licensed medical professional.

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