Early 17th century; earliest use found in Edward Topsell (d. 1625), Church of England clergyman and author. From classical Latin zȳthum from Hellenistic Greek ζῦθος, of unknown origin.
Definition of zythum in US English:
zythum
nounˈzʌɪθəm
In ancient Egypt: a kind of malt beer.
Origin
Early 17th century; earliest use found in Edward Topsell (d. 1625), Church of England clergyman and author. From classical Latin zȳthum from Hellenistic Greek ζῦθος, of unknown origin.