thyroid

American  

[thahy-roid] / ˈθaɪ rɔɪd /

adjective

1. of or relating to the thyroid gland.

2. of or relating to the largest cartilage of the larynx, forming the projection known in humans as the Adam's apple.

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noun

thyroids plural

1. thyroid gland.

2. the thyroid cartilage.

3. an artery, vein, etc., in the thyroid region.

4. Medicine/Medical. a preparation made from the thyroid glands of certain animals, used in treating hypothyroid conditions.

thyroid British  

/ ˈθaɪrɔɪd /

adjective

1. of or relating to the thyroid gland

2. of or relating to the largest cartilage of the larynx

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noun

1. See thyroid gland

2. Also: thyroid extract.  the powdered preparation made from the thyroid gland of certain animals, used to treat hypothyroidism

thyroid Cultural  

1. A large gland in the neck that functions in the endocrine system. The thyroid secretes hormones that regulate growth and metabolism.

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Other Word Forms

Derived Forms

• antithyroid
  adjective
• postthyroidal
  adjective
• prethyroid
  adjective
• thyroidal
  adjective
• thyroidless
  adjective

Inflected Forms

Nouns

• thyroids
  plural

Etymology

Origin of thyroid

1685–95; variant of thyreoid < Greek thyreoeidḗs shield-shaped, equivalent to thyre ( ós ) oblong shield (literally, doorlike object, equivalent to thýr ( a ) door + -eos adj. suffix) + -oeidēs -oid

Example Sentences

See Examples For:

thyroid thyroids

Scientists at Johns Hopkins University have uncovered how humans develop sharp central vision before birth, identifying a carefully timed interaction between a vitamin A derived molecule and thyroid hormones in the retina.

From Science Daily ● Jul. 9, 2026

Filipino women have a higher incidence of thyroid cancer, and stomach cancer has been more common among some Korean and Japanese people.

From Los Angeles Times ● Jun. 6, 2026

Russian scientists working with government agencies claim to have bioprinted human cartilage tissue and a mouse thyroid gland, with the aim of achieving human organ replacement by 2030.

From The Wall Street Journal ● May 29, 2026

Former US Attorney General Pam Bondi, who was removed from her role last month, has been diagnosed with thyroid cancer.

From BBC ● May 27, 2026

“I've got diabetes, high blood pressure, a hyperactive thyroid, and poor circulation in my legs. And she’s worried about a little caffeine.”

From "The Parker Inheritance" by Varian Johnson

After I discovered it was a thyroid problem, I went to a doctor who specialized in thyroids.

From Los Angeles Times ● Apr. 29, 2022

Government scientists, drawing on data from Nagasaki and Hiroshima, used to visit schools to check thyroids and radioactivity levels, recalled Peterson, another advocate.

From The Guardian ● Jun. 6, 2015

Yet when Japanese scientists and inspected the bodies of 38,000 children living in the Fukushima Prefecture, they found 36 percent had abnormal growths on their thyroids a year after the accident.

From Slate ● Apr. 18, 2013

Cats with overactive thyroids – which can lead to weight loss, increased appetite, hyperactivity and death – had higher blood levels of the chemicals, according to one small study led by Environmental Protection Agency scientists.

From Scientific American ● Sep. 25, 2012

Of course, the radioactive strontium they ate was concentrated in their bones, and the radioactive iodine was concentrated in their thyroids.

From "Cosmos" by Carl Sagan