thymus

[ thahy-muh s ]
/ ˈθaɪ məs /

noun, plural thy·mus·es, thy·mi [thahy-mahy] /ˈθaɪ maɪ/. Anatomy.

a ductless, butterfly-shaped gland lying at the base of the neck, formed mostly of lymphatic tissue and aiding in the production of T cells of the immune system: after puberty, the lymphatic tissue gradually degenerates.

Nearby words

  1. thymokinetic,
  2. thymol,
  3. thymoma,
  4. thymoprival,
  5. thymosin,
  6. thymus corpuscle,
  7. thymus gland,
  8. thymy,
  9. thyone,
  10. thyratron

Origin of thymus

1685–95; < New Latin < Greek thýmos warty excrescence, thymus

Also called thymus gland.

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for thymus


British Dictionary definitions for thymus

thymus

/ (ˈθaɪməs) /

noun plural -muses or -mi (-maɪ)

a glandular organ of vertebrates, consisting in man of two lobes situated below the thyroid. In early life it produces lymphocytes and is thought to influence certain immunological responses. It atrophies with age and is almost nonexistent in the adult

Word Origin for thymus

C17: from New Latin, from Greek thumos sweetbread

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for thymus

thymus

n.

gland near the base of the neck, 1690s, Modern Latin, from Greek thymos "a warty excrescence," used of the gland by Galen, literally "thyme," probably so called because of a fancied resemblance to a bunch of thyme (see thyme).

Online Etymology Dictionary, © 2010 Douglas Harper

Medicine definitions for thymus

thymus

[ thīməs ]

n. pl. thy•mus•es

A lymphoid organ that is located in the superior mediastinum and lower part of the neck and is necessary in early life for the normal development of immunological function.
The thymus of a calf or lamb.

The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Science definitions for thymus

thymus

[ thīməs ]

An organ of the lymphatic system located behind the upper sternum (breastbone). T cells (T lymphocytes) develop and mature in the thymus before entering the circulation. In humans, the thymus stops growing in early childhood and gradually shrinks in size through adulthood, resulting in a gradual decline in immune system function.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.