thymus

noun
thy·​mus | \ ˈthī-məs How to pronounce thymus (audio) \
variants: or thymus gland
plural thymuses also thymi\ ˈthī-​ˌmī How to pronounce thymi (audio) \

Definition of thymus

: a glandular structure of largely lymphoid tissue that functions especially in cell-mediated immunity by being the site where T cells develop, is present in the young of most vertebrates typically in the upper anterior chest or at the base of the neck, and gradually decreases in size and activity after puberty

Examples of thymus in a Sentence

Recent Examples on the Web The missing thymus is one of several effects of CHARGE. Jackie Rehwald, USA TODAY, "Child with no immune system is living in 'bubble' as he awaits a transplant," 31 Jan. 2020 Herbert wasn’t alone in his puzzlement over this mysterious and little-studied group of cells that keep turning up in unexpected places, from the thymus (a small gland in the chest where pathogen-fighting T cells mature) to the pancreas. Quanta Magazine, "Cells That ‘Taste’ Danger Set Off Immune Responses," 15 Nov. 2019 The thymus gland sits in the middle of the chest and is large in infants. Meredith Cohn, baltimoresun.com, "Rep. Elijah Cummings had a rare cancer. That he survived it for 25 years may be more rare.," 13 Nov. 2019 Miller, working at the University of London in the late 1950s and 1960s, identified a population of immune cells that develop in the thymus gland of mice—called T lymphocytes or T cells. Ewen Callaway, Scientific American, "Immune-Cell Pioneers Win Prestigious Lasker Medical Award," 10 Sep. 2019 Opponents, however, say that newer methods, including the use of thymus tissue from newborn infants who undergo heart surgeries, appear promising. oregonlive.com, "Donald Trump ends federal funding of research using fetal tissue," 6 June 2019 Opponents, however, say that newer methods, including the use of thymus tissue from newborn infants who undergo heart surgeries, appear promising. oregonlive.com, "Donald Trump ends federal funding of research using fetal tissue," 6 June 2019 Opponents, however, say that newer methods, including the use of thymus tissue from newborn infants who undergo heart surgeries, appear promising. oregonlive.com, "Donald Trump ends federal funding of research using fetal tissue," 6 June 2019 Opponents, however, say that newer methods, including the use of thymus tissue from newborn infants who undergo heart surgeries, appear promising. oregonlive.com, "Donald Trump ends federal funding of research using fetal tissue," 6 June 2019

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

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First Known Use of thymus

1578, in the meaning defined above

History and Etymology for thymus

New Latin, from Greek thymos warty excrescence, thymus

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Time Traveler for thymus

Time Traveler

The first known use of thymus was in 1578

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Statistics for thymus

Last Updated

6 Jun 2020

Cite this Entry

“Thymus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/thymus. Accessed 2 Jul. 2020.

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More Definitions for thymus

thymus

noun
thy·​mus | \ ˈthī-məs How to pronounce thymus (audio) \
variants: or thymus gland
plural thymuses also thymi\ -​ˌmī How to pronounce thymi (audio) \

Medical Definition of thymus

: a glandular structure of largely lymphoid tissue that functions in cell-mediated immunity by being the site where T cells develop, that is present in the young of most vertebrates typically in the upper anterior chest or at the base of the neck, that arises from the epithelium of one or more embryonic branchial clefts, and that gradually decreases in size and activity after puberty

More from Merriam-Webster on thymus

Rhyming Dictionary: Words that rhyme with thymus

Britannica.com: Encyclopedia article about thymus

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