thyroxine

noun
thy·​rox·​ine | \thī-ˈräk-ˌsēn, -sən\
variants: or thyroxin

Definition of thyroxine 

: 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

Your thyroid produces hormones like thyroxine and triiodothyronine, which influence many of your body’s systems, according to the Mayo Clinic. Zahra Barnes, SELF, "This Is When You Should Actually Worry About Heart Palpitations," 16 Jan. 2018 About 3 million French people, 80% of them women, take Levothyrox, which replaces the hormone thyroxine in patients with hypothyroidism. Yves Sciama, Science | AAAS, "France brings back a phased-out drug after patients rebel against its replacement," 27 Sep. 2017 Taken by about 3 million people in France alone, the drug replaces the hormone thyroxine in patients with the metabolic condition, hypothyroidism. Beth Mole, Ars Technica, "Police raid Merck pharmaceutical plant amid mysterious drug crisis," 4 Oct. 2017 Experts say at least some of the problems were likely caused by fluctuations in patients' thyroxine levels as a result of the switch—despite the bio-equivalence study. Yves Sciama, Science | AAAS, "France brings back a phased-out drug after patients rebel against its replacement," 27 Sep. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'thyroxine.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of thyroxine

1918, in the meaning defined above

History and Etymology for thyroxine

thyr- + oxy + indole

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Time Traveler for thyroxine

The first known use of thyroxine was in 1918

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More Definitions for thyroxine

thyroxine

noun
thy·​rox·​ine
variants: or thyroxin \thī-​ˈräk-​ˌsēn, -​sən \

Medical Definition of thyroxine 

: 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

More from Merriam-Webster on thyroxine

Britannica.com: Encyclopedia article about thyroxine

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