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IU

abbreviation

international unit

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Itza
IU
IUCD
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Cite this Entry

“IU.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/IU. Accessed 30 Nov. 2025.

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Medical Definition

IU

abbreviation
1
immunizing unit
2
international unit

More from Merriam-Webster on IU

Britannica.com: Encyclopedia article about IU

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