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
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.
The airline also said its domestic and international unit revenues are growing in the mid-single digits year over year. — Laya Neelakandan,michele Luhn, CNBC, 17 Mar. 2026 More than half of them required an initial dose of 5,000 international units (IU). — Angelica Stabile, FOXNews.com, 12 Nov. 2025 The table below spells them out in grams (g), milligrams (mg), micrograms (mcg), and international units (IU). — Lana Barhum, Verywell Health, 1 July 2026 However, taking calcium with high doses of vitamin D (long-term intake of doses larger than 4,000 international units (IUs) per day) can raise your risk for dangerously high calcium levels in your blood. — Kirstyn Hill, Health, 5 Feb. 2026 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

Rhymes for international unit

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Browse Nearby Words

international temperature scale
international unit
internecine
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Cite this Entry

“International unit.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/international%20unit. Accessed 7 Jul. 2026.

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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

More from Merriam-Webster on international unit

Britannica.com: Encyclopedia article about international unit

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