thyroxine

noun

thy·rox·ine thī-ˈräk-ˌsēn

-sən

variants or thyroxin

: an iodine-containing hormone C₁₅H₁₁I₄NO₄ that is an amino acid produced by the thyroid gland as a product of the cleavage of thyroglobulin, increases metabolic rate, and is used to treat thyroid disorders

called also T4

Examples of thyroxine 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.

This hormone sends signals to the thyroid to create the hormones triiodothyronine (T3) and thyroxine (T4). —

Dr. Roshini Raj, Health, 14 June 2024 These include thyroid-stimulating hormone, or TSH, which stimulates the thyroid gland to release two other hormones: triiodothyronine, or T3, and thyroxine, or T4. —

Brad Reisfeld, Discover Magazine, 12 Feb. 2024 Top up your vitamin D The hormone thyroxine helps to control our ability to produce energy. —

Georgia Day, Glamour, 1 Jan. 2024 The amino acid l-tyrosine will boost your metabolic rate and production of human growth hormone and thyroxine, while reducing depression and stress (19). —

Amber Smith, Discover Magazine, 6 Oct. 2023 See all Example Sentences for thyroxine

Word History

Etymology

alteration (by substitution of the suffix -ine entry 2 for -in entry 1) of earlier thyroxin, shortened from thyro-oxy-indol, from thyro- + oxy + indole

Note: The name was introduced by the American biochemist Edward Calvin Kendall (1886-1972) in "The thyroid hormone and its relation to the other ductless glands," Endocrinology, vol. 2 (1918), p. 90. The change of suffix was made when it was realized that the compound had an amino acid as a nucleus rather than indole, as Kendall had believed. (See A.T. Cameron, "Designation of thyroxine," Nature, vol. 119, June 25, 1927, p. 925.)

First Known Use

1918, in the meaning defined above

Time Traveler

The first known use of thyroxine was in 1918

See more words from the same year

Cite this Entry

Style

“Thyroxine.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/thyroxine. Accessed 22 Nov. 2024.

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Kids Definition

thyroxine

noun

thy·rox·ine

variants or thyroxin

thī-ˈräk-sən

-ˌsēn

: an iodine-containing hormone that is produced by the thyroid gland and is used to treat thyroid disorders

Medical Definition

thyroxine

noun

thy·rox·ine

variants or thyroxin

thī-ˈräk-ˌsēn, -sən

: an iodine-containing hormone C₁₅H₁₁I₄NO₄ that is an amino acid produced by the thyroid gland as a product of the cleavage of thyroglobulin, that increases the metabolic rate, and that is used to treat thyroid disorders

called also T4

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thyroxine

noun

Examples of thyroxine in a Sentence

Word History

Dictionary Entries Near thyroxine

Cite this Entry

Kids Definition

Medical Definition