Real Dictionary

I.O. in American English
abbreviation: indirect object

io in American English
noun: a small hawk, Buteo solitarius, having two plumage phases and occurring only on the island of Hawaii, where it is a rare species and the only living indigenous bird of prey

Io in American English 1
a maiden loved by Zeus and changed into a heifer by jealous Hera or, in some tales, by Zeus to protect her: she is watched by Argus and is driven to Egypt, where she regains human form
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 Egyptia

Io in American English 2
ionium
noun

Io in American English 3
the chemical symbol for: ionium

io in British English
the internet domain name for: British Indian Ocean Territory

Io in British English 1
noun: a maiden loved by Zeus and turned into a white heifer by either Zeus or Hera

Io in British English 2
noun: the innermost of the four Galilean satellites of Jupiter, displaying intense volcanic activity. Diameter: 3640 km; orbital radius: 422 000 km

Io in British English 3
the chemical symbol for: ionium

Io. in American English
abbreviation: Iowa