Dictionary.com
Thesaurus.com
Jump To:
  • io
    io
    noun
    a small, solitary hawk, Buteo solitarius, having two plumage phases and breeding only on the Island of Hawaii, where it is a rare species and the only indigenous bird of prey: classified as near threatened.
  • Io
    Io
    noun
    a woman who, being loved by Zeus, was transformed into a white heifer and was, at the wish of Hera, first guarded by Argus and later pursued through the world by a gadfly until she reached Egypt, where she resumed her true shape: identified by the Egyptians with Isis.
  • Io.
    Io.
    abbreviation
    Iowa.
  • I/O
  • I.O.
    I.O.
    abbreviation
    indirect object.

io

1 American  
[ee-oh] / ˈi oʊ /
Or 'io

noun

  • ios
    plural
  1. a small, solitary hawk, Buteo solitarius, having two plumage phases and breeding only on the Island of Hawaii, where it is a rare species and the only indigenous bird of prey: classified as near threatened.


Io 2 American  
[ahy-oh, ee-oh] / ˈaɪ oʊ, ˈi oʊ /

noun

  1. Classical Mythology. a woman who, being loved by Zeus, was transformed into a white heifer and was, at the wish of Hera, first guarded by Argus and later pursued through the world by a gadfly until she reached Egypt, where she resumed her true shape: identified by the Egyptians with Isis.

  2. Astronomy. a large volcanically active moon of the planet Jupiter.


Io 3 American  
[ahy-oh, ee-oh] / ˈaɪ oʊ, ˈi oʊ /

noun

  • Ios
    plural
  1. Io moth.


Io 4 American  
Symbol, Chemistry.
  1. ionium.


Io. 5 American  

abbreviation

  1. Iowa.


I/O 6 American  
I.O. 7 American  
Or IO,

abbreviation

  1. indirect object.


I/O 1 British  

abbreviation

  1. input/output

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Io 2 British  
/ ˈaɪəʊ /

noun

  1. Greek myth a maiden loved by Zeus and turned into a white heifer by either Zeus or Hera

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Io 3 British  
/ ˈaɪəʊ /

noun

  1. the innermost of the four Galilean satellites of Jupiter, displaying intense volcanic activity. Diameter: 3640 km; orbital radius: 422 000 km

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

io 4 British  

abbreviation

  1. British Indian Ocean Territory

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Io 5 British  

symbol

  1. ionium

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Io Scientific  
/ ī′ō,ē′ō /
  1. One of the four brightest satellites of Jupiter and the fifth in distance from the planet. It was first sighted by Galileo.

  2. See Note at moon


Other Word Forms

Noun Inflected Forms


Etymology

Origin of io

From Hawaiian ʿio


Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

Tan spent 24 years at Apple, most recently as vice president of product design for the iPhone and Apple Watch, before co-founding io Products, which OpenAI acquired for roughly $6.5 billion in 2025.

From Barron's ● Jul. 10, 2026

Along with OpenAI, Apple is suing io Products, the design startup founded by Jony Ive, a long-time Apple executive.

From BBC ● Jul. 10, 2026

Tan left Apple to found io Products alongside Jony Ive, Apple’s former chief design officer, and other leaders.

From MarketWatch ● Jul. 10, 2026

OpenAI started its consumer-hardware division last May, when it paid $6.5 billion in stock to acquire io, an AI company led by former Apple designer Jony Ive, and hired its staff of roughly 55.

From The Wall Street Journal ● May 5, 2026

Wasn't quite midday so the heat wasn’t overbearing and there weren’t no heat waves across the fields io make the eye see things funny.

From "Life Is So Good" by George Dawson

This inner gap likely helped capture and preserve Io, Europa, and Ganymede as they moved through the disk.

From Science Daily ● Jul. 27, 2026

Scientists have long theorized that Jupiter's four large moons -- Io, Europa, Ganymede, and Callisto -- originated from a similar disk surrounding the young planet billions of years ago.

From Science Daily ● Oct. 29, 2025

“Juno had two really close flybys of Io during Juno’s extended mission,” Scott Bolton of the Southwest Research Institute in San Antonio, the mission’s principal investigator, said in a statement.

From Salon ● Feb. 3, 2025

The acid yellow moon Io that orbits Jupiter may be less than 30% the size of Earth, but is considered the most volcanic body in our solar system.

From Salon ● Feb. 3, 2025

Volcanoes inject debris into the atmospheres of the Earth and Io.

From "Cosmos" by Carl Sagan

They are, however, frequently abbreviated thus: Iowa, Ia. or Io.;

From Higher Lessons in English A work on English grammar and composition by Brainerd Kellogg

Tuesday’s Google I/O developer conference failed to pack the sizzle that some investors were hoping for.

From MarketWatch ● May 20, 2026

The order is for production of wafer-level test and burn-in of silicon photonics integrated circuits, used in data center optical interconnects and emerging optical I/O architectures for AI processors, according to Aehr.

From Barron's ● Apr. 3, 2026

Google Chief Executive Sundar Pichai lauded a Gemini win on stage at Google’s I/O conference last year.

From The Wall Street Journal ● Jan. 22, 2026

Next month, it’ll kick off its always-exciting Worldwide Developers Conference, likely with as many A.I. mentions as Google’s recent I/O had, if not more.

From Slate ● May 24, 2024

In Great Britain, `fred', `jim' and `sheila' are common metasyntactic variables because their uppercase versions were official names given to the 3 memory areas that held I/O status registers on the lovingly-remembered BBC Microcomputer!

From The Jargon File, Version 4.2.2, 20 Aug 2000 by Guy L. Steele

The senior coalition officer said the insurgents who supported the Qatar process “didn’t do a good I.O. campaign to sell it to their people.”

From New York Times ● Oct. 2, 2012

Mr. Green next day notified the Canadian Trades and Labor Congress that it must expel 30,000 C. I.O. members or renounce 120,000 A. F. of L. members.

From Time Magazine Archive

Between A. F. of L. and C. I.O. there still exists a thin, technical tie: the rebellious C. I. O. unions were suspended last year but they have not yet been expelled.

From Time Magazine Archive

To these three the President added Sidney Hillman, pink-cheeked, blond, curly-haired, 53, chief of Amalgamated Clothing Workers of America, vice president of C. I.O., a "labor statesman," no bumbler, coldly intellectual.

From Time Magazine Archive

I see them shaking their fists in the face of the parietal tutor.—Oration before H.L. of I.O. of O.F.,

From A Collection of College Words and Customs by Benjamin Homer Hall

Post-mortem examinations are to be carried out on Tuesday on two teenagers from Dublin who died on the Greek island of Ios.

From BBC ● Jul. 3, 2023

In October, they interrogated a submarine cable that connects the islands of Santorini and Ios.

From Science Magazine ● Dec. 8, 2021

He met Fiona Moore, the woman who would become his wife, on the Greek island of Ios in the early 1990s.

From New York Times ● Dec. 27, 2016

Last summer, I had lunch in a beach-side taverna on the island of Ios, which I had last visited when it was a hippy haven in the 1970s.

From BBC ● Jul. 24, 2015

He was buried in Ios, and this is his epitaph: 'Here the earth covers the sacred head of divine Homer, the glorifier of hero-men.'

From Hesiod, the Homeric Hymns, and Homerica by Hugh G. (Hugh Gerard) Evelyn-White

This week the app overtook WeChat and TikTok to become the most-downloaded app for Apple and ios devices in China, though its popularity is not entirely due to merit.

From The Guardian ● Feb. 15, 2019

There are a lot of closeups and  difficult-to-decipher geometry, but the intent here is clear — Sony is ios going to show us what the PS4 actually looks like.

From Forbes ● May 20, 2013

Android is much better, in my opinion, because it is not afraid to make drastic changes to its system. ios has looked similar since the start.

From Time ● Apr. 21, 2013

Only the brooding golden backlighting that makes theaters out of Parrish's scenar ios bespeaks a pre-neon sensibility.

From Time Magazine Archive

The price is 28,000 10000 in fives and ios 18000 50 and zoos.

From Time Magazine Archive

Random Word

Spin the wheel and learn a new word!

Get a word

Vocabulary.com logo
by dictionary.com

Just like flashcards, but way more fun

Don't take our word for it. Leave the boring studying behind and join VocabTrainer today. You'll learn even faster and never look back.

Take me to Vocabulary.com