Io Definition
 īō, ēō 
    noun
  
 A maiden loved by Zeus and changed into a heifer by jealous Hera or, in some tales, by Zeus to protect her.
 Webster's New World 
The third largest satellite of Jupiter: discovered in 1610 by Galileo and found in 1979 to be volcanically active.
 Webster's New World 
A type of moth, the io moth.
Wiktionary 
    symbol
  
 Ionium.
 Webster's New World 
    interjection
  
 An exclamation of joy or triumph.
 Wiktionary 





