international unit

noun

: a quantity of a biologically active substance (such as a vitamin) that produces a particular biological effect agreed upon as an international standard

Examples of international unit in a Sentence

Recent Examples on the Web
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People who took 2,000 international units (IUs) of vitamin D3 per day lost less of their telomeres over time than people who took a placebo, the researchers found. Jamie Ducharme, Health, 29 May 2025 For the study, researchers divided the subjects into four groups, with one group receiving 2,000 international units (IU) of vitamin D3 (a common form of D supplement) and 1 gram of omega-3 fatty acid per day. Tom Gavin, EverydayHealth.com, 27 May 2025 Moreover, high-dose vitamin E supplements, which are defined as more than 400 international units (IU) per day, may be harmful.10 5. Melissa Nieves, Verywell Health, 2 May 2025 To do so, squeeze the contents of a 1,000 international units (IU) liquid vitamin E capsule directly onto your tongue. Anna Giorgi, Verywell Health, 26 Mar. 2025 See All Example Sentences for international unit

Word History

First Known Use

1921, in the meaning defined above

Time Traveler
The first known use of international unit was in 1921

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Cite this Entry

“International unit.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/international%20unit. Accessed 4 Jun. 2025.

Medical Definition

international unit

noun
: the amount of specific physiological activity of a standardized preparation (as of a vitamin) that is agreed upon as an international standard especially for comparison with other biologicals containing the substance in impure form or with a related biologically active substance
also : the amount of the biologically active substance in the standard amount of the preparation producing this activity

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