Io or io has several meanings:

May refer to a deity:

• Io (mythology), the daughter of Inachus, a river god, in Greek mythology.
• Io the Parentless (), Māori god.
• Io (Dungeons & Dragons), the Father God of Dragonkind in Dungeons and dragons.
• Blind Io, King of all Gods in Terry Pratchett's Discworld series.

In music:

• Io (indie rock band), an indie rock band from San Francisco, California.
• Io (hardcore band), a pummeling hardcore band from Pittsburgh, Pennsylvania
• Io (Loredana Bertè), a Loredana Bertè album.
• Io (Project Pitchfork), an album by German industrial music artists, Project Pitchfork.

Io may also refer to:

• Io (moon), a moon of Jupiter.
• 85 Io, an asteroid.
• Io island (Iwo Jima), a volcanic island in Japan.
• Io (butterfly), a species of yellow butterfly.
• Io programming language, a prototype-oriented programming language made by Steve Dekorte.
• Io (voievodal title particle), particle preceding the name of Romanian voievods (rulers) during the middle ages.
• 'Io, the local name of the Hawaiian Hawk.

Finally, io is the ISO 639 alpha-2 code for the Ido language.

See also

• IO
• .io, the ccTLD for the British Indian Ocean Territory.

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