Io

Io, in astronomy

Io (ī`ō), in astronomy, one of the 39 known moons, or natural satellites, of Jupiter. Io is subject to Jupiter's enormous tidal forces and is, as a result, the most volcanically active body in the solar system.

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Io, in Greek mythology

Io, in Greek mythology, daughter of Inachus, king of Argos. She was loved by Zeus, who, to protect her from Hera's jealousy, changed her into a white heifer. Hera, however, was not deceived; she claimed the heifer and sent Argus to guard it. When Hermes killed Argus, Hera tormented Io with a gadfly which drove her across Europe and through Asia, until she was finally allowed to rest in Egypt. There Zeus returned her to human form, and she bore his child Epaphus. Io has been identified with the Egyptian goddess Isis.

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Io

In Greek mythology, the daughter of the river god Argos. Io drew Hera's jealousy when Zeus fell in love with her. Zeus changed her into a white heifer to protect her. Hera sent the many-eyed creature Argus to watch over the heifer, but Zeus sent Hermes to lull Argus to sleep and kill him. Hera then sent a gadfly to pursue Io, who fled across Europe and crossed the bodies of water later named the Ionian Sea and the Bosporus (“Ford of the Cow”) in her honour. When she arrived in Egypt she resumed her original form. She was later identified with the Egyptian goddess Isis.

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IO

See I/O.

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Io¹

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

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Io²

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

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Io

seduced by Jupiter in form of a cloud. [Rom. Myth.: Metamorphoses]

See : Seduction

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Io

having been changed into a heifer by Zeus, pestered by gadfly sent by Hera. [Gk. Myth.: Espy, 292]

See : Suffering

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Io

changed into heifer by Zeus because of Hera’s jealousy. [Gk. Myth.: Zimmerman, 137]

See : Transformation

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1.	(humor, abuse)	IO - Idiotic operator.
2.	(networking)	io - The country code for British Indian Ocean territory.