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

But when I looked into it more, I discovered it also happens to some woman who have other autoimmune diseases like rheumatoid arthritis and thyroid problems.

From BBC ● Aug. 28, 2026

"I was supposed to go for a thyroid check-up in January," Vasile, a 56-year-old housewife, told AFP, saying she used the money instead for food and the electricity bill.

From Barron's ● Aug. 6, 2026

She was diagnosed in 2022 with anaplastic thyroid cancer and underwent chemotherapy and radiation, but the cancer persisted.

From Los Angeles Times ● Jul. 18, 2026

Then thyroid hormones drive the remaining blue cones to convert into red and green cones.

From Science Daily ● Jul. 9, 2026

My zoology thesis was a functional analysis of the thyroid gland of the three-toed sloth.

From "Life of Pi" by Yann Martel

With a million better things to do, we race the beagle to the vet, who mutters a bunch of things about thyroids and further tests.

From Los Angeles Times ● Dec. 21, 2018

Goop wanted to publish articles about autoimmune diseases and infrared saunas and thyroids, and now it can, on its own terms — sort of.

From New York Times ● Jul. 25, 2018

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

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