Pronunciation (UK) IPA (key): /ˈɡɪɡəbaɪt/ (US) IPA (key): /ˈɡɪɡəbaɪt/ or /ˈd͡ʒɪɡəbaɪt/ Audio (UK)(file) Noun Singular gigabyte Plural gigabytes (countable) One billion (1,000,000,000) bytes My new computer has 100 gigabytes of memory and a 200 gigabyte hard drive.Wikiwand - on Seamless Wikipedia browsing. On steroids.Remove ads