Biannual
/ˌbaɪˈæn.ju.əl/noun
Happening twice a year or every two years, depending on context.
Did you know?Unlike truly occult-sounding words, biannual has no dark ancient ritual origin—it comes from straightforward Latin roots, but its ambiguity has made it a notorious source of confusion in schedules, contracts, and official language.
Etymological Timeline
Latin roots
Latin
bis + annus
“twice + year”
Late Latin
Latin
biannualis
“occurring twice a year”
16th–17th Century
English
biannual
“occurring twice in a year”
Modern English
English
biannual
“happening twice a year; sometimes used ambiguously for every two years”
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