T cell
noun
: any of several lymphocytes (such as a helper T cell) that differentiate in the thymus, possess highly specific cell-surface antigen receptors, and include some that control the initiation or suppression of cell-mediated and humoral immunity (as by the regulation of T and B cell maturation and proliferation) and others that lyse antigen-bearing cells : t lymphocyte
The immature lymphoid cell, in turn, can be processed into a B cell, which makes infection-fighting antibodies, or a T cell, which recognizes foreign tissue and virally infected cells and directs the activities of the rest of the immune system.—
Gina Kolata
Gina KolataT cells recognize antigen only in association with cell surface molecules encoded by the major histocompatibility complex …—Miranda Robertson
see helper t cell, killer t cell compare b cell
Miranda RobertsonExamples of T cell in a Sentence
Recent Examples on the Web
But those preclinical studies uncovered how T cells, specialized white blood cells that are programmed to recognize and exterminate threats like cancer, are more active in the morning.
—Brenda Goodman, CNN Money, 6 Feb. 2026
Once fully accredited, Dell Children's will be able to do allogeneic transplants, which uses donor stem cells, as well as gene therapies and CAR T cell therapies.
—Nicole Villalpando, Austin American Statesman, 5 Feb. 2026
These parallels suggest that heart failure induces T cells to behave similarly to those in autoimmune disease rather than those that heal injuries.
—Shyam Bansal, The Conversation, 5 Feb. 2026
Because the brain has ordered the macrophages to create an immunosuppressive shield, the T cells lose their energy, stop multiplying and fail to recognize the cancer as a threat.
—Jacek Krywko, Scientific American, 4 Feb. 2026
See All Example Sentences for T cell
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Brenda Goodman, CNN Money, 6 Feb. 2026
Once fully accredited, Dell Children's will be able to do allogeneic transplants, which uses donor stem cells, as well as gene therapies and CAR T cell therapies.
—Nicole Villalpando, Austin American Statesman, 5 Feb. 2026
These parallels suggest that heart failure induces T cells to behave similarly to those in autoimmune disease rather than those that heal injuries.
—Shyam Bansal, The Conversation, 5 Feb. 2026
Because the brain has ordered the macrophages to create an immunosuppressive shield, the T cells lose their energy, stop multiplying and fail to recognize the cancer as a threat.
—Jacek Krywko, Scientific American, 4 Feb. 2026
See All Example Sentences for T cell
Cite this Entry
“T cell.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/T%20cell. Accessed 14 Feb. 2026.
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