Electro- : A prefix or combining form signifying pertaining to electricity, produced by electricity, producing or employing electricity, etc.; as, electro-negative; electro-dynamic; electro-magnet.

Example:
What is the difference between electro, electronic, and electronica?

Taxonomy
Electro music, Planet Rock, Hashim, free encyclopedia, origins, funk, electrofunk, vocals, Afrika Bambaataa, Mainstream popularity, mid 1980s, synthetic, the 1990s, producer, Nordic countries, electroempire, drum machine, characteristics.

Defination from the web:
Electro music, a genre characterized by cheesy, funky synthesizer tones, vocoder vocal effect, the 808 drum machine.