Definition of giga- in US English:

giga-

combining form

  • 1(in units of measurement) denoting a factor of 10⁹

    ‘gigahertz’
  • 2Computing
    Denoting a factor of 2³⁰.

Origin

From Greek gigas ‘giant’.

Pronunciation

giga-

/ˈɡiɡə//ˈɡɪɡə/