hyperthyroidism

noun

hy·​per·​thy·​roid·​ism ˌhī-pər-ˈthī-ˌrȯi-ˌdi-zəm How to pronounce hyperthyroidism (audio)
: excessive functional activity of the thyroid gland
also : the resulting condition marked especially by increased metabolic rate, enlargement of the thyroid gland, rapid heart rate, and high blood pressure

Examples of hyperthyroidism in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
In rare scenarios, those wakeups might be tied to conditions like sleep apnea or hyperthyroidism. — Erica Sloan, SELF, 24 Feb. 2026 People with diabetes, epilepsy, heart rhythm concerns, high blood pressure, glaucoma, or hyperthyroidism need to talk with their doctor before taking them. — Kara Smythe, EverydayHealth.com, 15 May 2026 Hypothyroidism is an underactive thyroid gland, and hyperthyroidism is an overactive thyroid gland. — Colleen Doherty, Verywell Health, 18 Dec. 2025 In 2009, Li was diagnosed with hyperthyroidism, or an overactive thyroid. — Chris Lau, CNN Money, 19 May 2026 See All Example Sentences for hyperthyroidism

Word History

Etymology

International Scientific Vocabulary

First Known Use

circa 1900, in the meaning defined above

Time Traveler
The first known use of hyperthyroidism was circa 1900

Rhymes for hyperthyroidism

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Browse Nearby Words

hyperthyroid
hyperthyroidism
hypertonia
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Cite this Entry

“Hyperthyroidism.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/hyperthyroidism. Accessed 7 Jul. 2026.

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Kids Definition

hyperthyroidism

noun
hy·​per·​thy·​roid·​ism ˌhī-pər-ˈthī-ˌrȯid-ˌiz-əm How to pronounce hyperthyroidism (audio)
-rəd-
: abnormally high activity of the thyroid gland
also : the resulting abnormal state of health
hyperthyroid
-ˌrȯid
adjective

Medical Definition

hyperthyroidism

noun
hy·​per·​thy·​roid·​ism -ˌrȯid-ˌiz-əm, -rəd- How to pronounce hyperthyroidism (audio)
: excessive functional activity of the thyroid gland
also : the resulting condition marked especially by increased metabolic rate, enlargement of the thyroid gland, rapid heart rate, and high blood pressure

called also thyrotoxicosis

see graves' disease

More from Merriam-Webster on hyperthyroidism

Britannica.com: Encyclopedia article about hyperthyroidism

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