Io

1 of 2

noun

: 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

First Known Use

Noun

1563, in the meaning defined above

Time Traveler
The first known use of Io was in 1563

Dictionary Entries Near Io

Cite this Entry

“Io.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Io. Accessed 29 Mar. 2024.

Medical Definition

Io

symbol
ionium

More from Merriam-Webster on Io

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