What are “Biannual,” “Biennial,” and “Semiannual”? Rules of Usage

There’s actually no difference between biannual vs. semiannual. They both describe twice-yearly events. Biennial, on the other hand, means every other year.
“Biannual” is an adjective used to describe events occurring twice a year. In order to fully understand this term, we need to know where it derives from. The prefix “bi-,” meaning twice, comes from Latin, while “annual” refers to one year.

Avoid Bi- & Tri- In Frequency Words

Annual Definition & Meaning

Chapter 25: Usage Write for Business

Biannual: Unveiling the Differences: Semiannual vs Biannual - FasterCapital

Difference between eBook

Anniversary Latin-Derived Term Other Terms Comments: Biennial Every Second Year, PDF

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Biannual: Unveiling the Differences: Semiannual vs Biannual - FasterCapital

Biannual vs. Biennial: What's the Difference? - Turner Proofreading

Semiannual' vs 'Biannual': What's the Difference?

Strategii conversationale în limba engleză by Aurelian Paun - Issuu