rheumatoid factor

[roo-muh-toid fak-ter]

noun

Biochemistry.

1. an antibody that is found in the blood of many persons with rheumatoid arthritis and that reacts against globulins in the blood.

Word History and Origins

Origin of rheumatoid factor¹

First recorded in 1945–50

Example Sentences

They also found antibodies against a protein called rheumatoid factor and others that help with blood clotting.

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My mother’s conditions are not hereditary, nor are they related to migraine, but neurologists still want to test my blood for rheumatoid factor and other traces of autoimmune disease.

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Blood tests check for specific markers of the disease, such as a substance called rheumatoid factor, and Zieman's results were negative, something that occurs occasionally.

Read more on Seattle Times