osteoarthritis

n. degenerative arthritis which occurs especially in elderly people (Medicine)

Osteoarthritis / Osteoarthrosis (OA, also known as degenerative arthritis, degenerative joint disease, arthrosis or in more colloquial terms "wear and tear"), is a condition in which low-grade inflammation results in pain in the joints, caused by wearing of the cartilage that covers and acts as a cushion inside joints. As the bone surfaces become less well protected by cartilage, the patient experiences pain upon weight bearing, including walking and standing. Due to decreased movement because of the pain, regional muscles may atrophy, and ligaments may become more lax. OA is the most common form of arthritis. The word is derived from the Greek word "osteo", meaning "of the bone", "arthro", meaning "joint", and "itis", meaning inflammation, although many sufferers have little or no inflammation.
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Osteoarthritis, which is also known as osteoarthrosis or degenerative joint disease, is a progressive disorder of the [more]Osteoarthritis - Community and Resources

Noun
1. chronic breakdown of cartilage in the joints; the most common form of arthritis occurring usually after middle age
(synonym) degenerative arthritis, degenerative joint disease
(hypernym) arthritis

Type of arthritis caused by inflammation, breakdown and eventual loss of the cartilage of the joints. For more information on this common type of arthritis, please see the MedicineNet site on OSTEOARTHRITIS.