hyperthyroidism

American  

[hahy-per-thahy-roi-diz-uhm] / ˌhaɪ pərˈθaɪ rɔɪˌdɪz əm /

noun

Pathology.

1. overactivity of the thyroid gland.

2. a condition resulting from this, characterized by increased metabolism and exophthalmos.

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hyperthyroidism British  

/ ˌhaɪpəˈθaɪrɔɪˌdɪzəm /

noun

1. Also called: thyrotoxicosis.  overproduction of thyroid hormone by the thyroid gland, causing nervousness, insomnia, sweating, palpitation, and sensitivity to heat See exophthalmic goitre

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hyperthyroidism Scientific  

/ hī′pər-thī′roi-dĭz′əm /

1. An abnormality of the thyroid gland characterized by excessive production of thyroid hormone, which can result in an increased basal metabolic rate, causing weight loss, heart palpitations, and tremors.

2. Compare hypothyroidism

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Other Word Forms

Derived Forms

• hyperthyroid
  adjective

Etymology

Origin of hyperthyroidism

First recorded in 1895–1900; hyper- + thyroid + -ism

Example Sentences

How did having hyperthyroidism compare with the many physical injuries you’ve dealt with in your life?

From The Wall Street Journal • May 4, 2026

Though she was “a little freaked out” to hear the words “autoimmune disease” from her doctor, Luddington said they reassured her that Hashimoto’s hyperthyroidism is a “very common” disorder.

From Los Angeles Times • Aug. 7, 2025

She had all the symptoms of hyperthyroidism, and I had simply not seen it.

From New York Times • Jun. 7, 2023

And she has since developed fibromyalgia and Graves’ disease, an autoimmune condition that causes hyperthyroidism.

From Scientific American • Sep. 22, 2022

Auricular fibrillation may occur in hearts which are suffering from valvular lesions, especially mitral stenosis, and may occur in syphilitic hearts, in various sclerotic conditions of the heart, and in hyperthyroidism.

From Disturbances of the Heart by Osborne, Oliver T. (Oliver Thomas)