How to Use Biannual, biennial and semiannual Correctly - GRAMMARIST
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WEBBiannual, biennial and semiannual. | Grammarist. | Usage. Biannual is an adjective which means occurring twice a year, the adverb form is biannually. Biannual is derived from the prefix bi-, which means two, twice, double, doubly, as it comes from the Latin bi-, meaning twice, double, and annual comes from the Old French twelfth century word ...
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