Look up 
-io, 
IO, 
Io, or 
io in Wiktionary, the free dictionary.
 
 
Io most commonly refers to:
- Io (moon), a moon of Jupiter
- Io (mythology), daughter of Inachus in Greek mythology, and lover of Zeus who was turned into a cow
Io, IO, iO, I/O, i/o, or i.o. may also refer to: