rheumatoid factor


Definition of rheumatoid factor

: an autoantibody of high molecular weight that reacts against IgG immunoglobulins and is often present in rheumatoid arthritis

Examples of rheumatoid factor in a Sentence

Recent Examples on the Web The doctor on call had the presence of mind to do a rheumatoid factor test, which tests for a type of protein that your immune system produces that can attack healthy tissue. Natasha Lavender, SELF, "This Is What Rheumatoid Arthritis Remission Really Feels Like," 15 Oct. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'rheumatoid factor.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of rheumatoid factor

1949, in the meaning defined above

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The first known use of rheumatoid factor was in 1949

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Cite this Entry

“Rheumatoid factor.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/rheumatoid%20factor. Accessed 21 Jan. 2021.

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rheumatoid factor


Medical Definition of rheumatoid factor

: an autoantibody of high molecular weight that reacts against immunoglobulins of the class IgG and is often present in rheumatoid arthritis

More from Merriam-Webster on rheumatoid factor

Britannica.com: Encyclopedia article about rheumatoid factor

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