thyroid

1 of 2

noun

thy·​roid ˈthī-ˌrȯid How to pronounce thyroid (audio)
1
: a large bilobed endocrine gland of vertebrates lying at the anterior base of the neck and producing especially the hormones thyroxine and triiodothyronine
2
: a preparation of the thyroid gland of various domestic animals used in treating thyroid disorders

thyroid

2 of 2

adjective

thy·​roid ˈthī-ˌrȯid How to pronounce thyroid (audio)
variants or less commonly thyroidal
1
a
: of, relating to, or being the thyroid gland
b
: suggestive of a disordered thyroid
a thyroid personality
2
: of, relating to, or being the chief cartilage of the larynx

Examples of thyroid in a Sentence

Recent Examples on the Web
Noun
Ashton, kvetching about his thyroid medication, fares somewhat better. Jordan Hoffman, EW.com, 2 July 2024 The condition, which affects 2 to 3 of every 1,000 children, usually causes hearing loss, but sometimes also thyroid and balance problems. Mark Johnson, Washington Post, 17 June 2024
Adjective
Arizona's top attorney sued a thyroid drug maker, saying the company lied about the potency of its medication and the harmful effects on consumers. Taylor Seely, The Arizona Republic, 30 Dec. 2022 Today, iodine deficiencies are less common, with thyroid dysfunction from iodine deficiency affecting about 30 percent of the world. Anna Funk, Discover Magazine, 6 June 2021 See all Example Sentences for thyroid 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'thyroid.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

Noun

short for thyroid gland — more at thyroid entry 2

Adjective

borrowed from New Latin thyroīdēs, shortened from thyreoīdēs, borrowed from Greek thyreoeidḗs "shield-shaped (of the cartilage in the larynx)," from thyreós "stone put against a door to keep it shut, oblong shield" (probably originally noun derivative of an adjective meaning "shaped like a door," from thýra "door" + -eos, suffix of appurtenance) + -oeidēs -oid entry 2 — more at door

Note: The form thyroīdēs presumably arose because the word was taken as directly derived from thýra "door," rather than from thyreós. The word thyroeidḗs "like a door" is marginally attested in ancient Greek.

First Known Use

Noun

1787, in the meaning defined at sense 1

Adjective

circa 1741, in the meaning defined at sense 1a

Time Traveler
The first known use of thyroid was circa 1741

Dictionary Entries Near thyroid

Cite this Entry

“Thyroid.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/thyroid. Accessed 20 Jul. 2024.

Kids Definition

thyroid

1 of 2 adjective
thy·​roid ˈthī-ˌrȯid How to pronounce thyroid (audio)
: of, relating to, or being the thyroid gland

thyroid

2 of 2 noun
: a large endocrine gland at the base of the neck of most vertebrates that produces iodine-containing hormones (as thyroxine) that affect growth, development, and metabolism

called also thyroid gland

Medical Definition

thyroid

1 of 2 adjective
thy·​roid ˈthī-ˌrȯid How to pronounce thyroid (audio)
variants also thyroidal
1
a
: of, relating to, affecting, or being the thyroid gland
thyroid disorders
2
: of, relating to, or being the thyroid cartilage

thyroid

2 of 2 noun
1
: a large bilobed endocrine gland of craniate vertebrates that arises as a median ventral outgrowth of the pharynx, lies in the anterior base of the neck or anterior ventral part of the thorax, is often accompanied by lateral accessory glands sometimes more or less fused with the main mass, and produces especially the hormones thyroxine and triiodothyronine

called also thyroid gland

2
: a preparation of the thyroid gland of various domesticated food animals (as pigs) containing approximately ¹/₁₀ percent of iodine combined in thyroxine and used in treating thyroid disorders

called also thyroid extract

More from Merriam-Webster on thyroid

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