What does synovitis mean?
Synovitis is inflammation of the synovium, the thin membrane that lines a joint. The synovium normally produces synovial fluid, which lubricates the joint and supports its movement, but inflammation can make this lining swell and cause pain, tenderness, stiffness, and restricted motion. Synovitis may occur in any joint, with the knee and wrist among those commonly affected, and it can be acute or chronic. Doctors may use it when examining a swollen joint, reviewing imaging results, or investigating conditions such as rheumatoid arthritis. The term should not be confused with arthritis, which is broader: arthritis can include inflammation of several joint structures, whereas synovitis identifies inflammation specifically involving the synovial lining. Although people sometimes use the two terms interchangeably, the distinction can be clinically important when identifying the affected tissue and underlying cause.
nounInflammation of the synovium, the membrane that lines a joint and produces synovial fluid. Synovitis may cause pain, swelling, stiffness, and restricted movement in the affected joint.
- Inflammation of the synovial membrane lining a joint, often associated with pain, swelling, stiffness, and reduced mobility.
"The scan showed synovitis in her knee, consistent with an inflamed joint lining."
"Persistent synovitis in the wrist led the specialist to recommend further imaging."
"In children, transient synovitis may cause sudden hip pain and difficulty walking."
The standard medical plural follows the usual formation of nouns ending in -itis.
"The radiographs showed synovitides in both knees."
Synovitis takes its name from the synovium, the delicate joint lining whose swelling can turn an ordinary movement into pain.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does synovitis come from?
The word combines Greek syn-, meaning “together,” with a form related to Latin synovia, a term for lubricating joint fluid, and the suffix -itis, meaning “inflammation.” The underlying word for joint fluid was borrowed into Latin from Greek synovia, itself associated with syn-, “together.” Modern medical usage developed “synovitis” by applying the inflammation suffix to the synovial joint-lining vocabulary.
Related word forms
How synovitis is actually used
This is chiefly a clinical term. It may describe inflammation associated with injury, infection, inflammatory disease, or prolonged mechanical irritation; it is not synonymous with arthritis in every clinical context.
Easily confused with synovitis
Arthritis is the broader term for inflammation of a joint, whereas synovitis specifically denotes inflammation of the joint's synovial lining.