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

Each day, most adults need about 600 international units (IU) of vitamin D, which can be found in sunlight and in certain foods, including mushrooms, fish, and dairy.9 Women need about 1.1 grams of omega-3 fatty acids daily, while men need about 1.6 grams. —Brian Mastroianni, Health, 12 Mar. 2025

Walgreens’ international unit, which operates more than 3,000 retail stores abroad, booked $6.43 billion in sales in the fiscal first quarter. —Annika Kim Constantino, CNBC, 10 Jan. 2025

It's typically measured in international units (IU) or micrograms (mcg), and dosages aren't broken down by vitamin D type. —Lindsey Desoto, Health, 23 Dec. 2024

Specifically, consuming 2,000 IU (international units) a day of supplemental vitamin D3 without calcium over the course of more than five years did not reduce total fractures, hip, wrist or pelvic fractures when compared with taking a daily placebo, according to the study. —Jacqueline Howard, CNN, 17 Dec. 2024

Word History

First Known Use

1921, in the meaning defined above

Rhymes for international unit

• lunate
• multiunit
• subunit

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