B cell

noun

: any of the lymphocytes that have antigen-binding antibody molecules on the surface, that comprise the antibody-secreting plasma cells when mature, and that in mammals differentiate in the bone marrow : b lymphocyte
The glycoproteins produced by B cells, called antibodies or immunoglobulins, recognize and bind free antigens and are responsible for humoral immunity …Haruo Saito et al.
helper T cells that induce the proliferation of the antibody-producing B cells.N. A. Mitchison
… patients have no mature B cells circulating in the bloodstream and no antibodies to fight off infections.Jean Marx
compare t cell

Examples of B cell in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Both T cells and B cells contributed to the immune response, suggesting the vaccine provided broad, multi-arm immunity. New Atlas, 9 Oct. 2025 For decades, scientists thought self-tolerance was primarily established in the parts of the body that make immune cells, such as the thymus for T cells and the bone marrow for B cells. Aimee Pugh Bernard, The Conversation, 6 Oct. 2025 Progression to rheumatoid arthritis in at-risk individuals is defined by systemic inflammation and by T and B cell dysregulation. Hannah Millington, MSNBC Newsweek, 24 Sep. 2025 To find those powerful antibodies, scientists sort through B cells, a type of white blood cell that makes millions of different antibodies against a particular pathogen. Tara Haelle, Scientific American, 23 Sep. 2025 See All Example Sentences for B cell

Word History

Etymology

B probably from bursa-derived (produced by the bursa of Fabricius)

First Known Use

1962, in the meaning defined above

Time Traveler
The first known use of B cell was in 1962

Browse Nearby Words

Cite this Entry

“B cell.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/B%20cell. Accessed 17 Oct. 2025.

Kids Definition

B cell

noun
ˈbē-ˌsel
: any of the lymphocytes that produce antigen-binding antibodies and that arise and mature in the bone marrow compare t cell

Medical Definition

B cell

noun
: any of the lymphocytes that have antigen-binding antibody molecules on the surface, that comprise the antibody-secreting plasma cells when mature, and that in mammals differentiate in the bone marrow

called also B lymphocyte

compare t cell

More from Merriam-Webster on B cell

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