Io

1 of 2

noun

ˈī-(ˌ)ō How to pronounce Io (audio)
: a maiden loved by Zeus and changed by him into a heifer so that she might escape the jealous rage of Hera

I/O

2 of 2

abbreviation

input/output

Word History

Etymology

Noun

Latin, from Greek Iō

First Known Use

Noun

1563, in the meaning defined above

Time Traveler
The first known use of Io was in 1563

Phrases Containing Io

Dictionary Entries Near Io

in-your-face

Io

I/O

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Cite this Entry

“Io.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Io. Accessed 5 Nov. 2024.

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Medical Definition

Io

symbol
ionium

More from Merriam-Webster on Io

Britannica.com: Encyclopedia article about Io

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