Biannual vs. Semiannual vs. Biennial

When to Use Biannual vs. Semiannual vs. Biennial

“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.

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What does “biannually” mean?

“Biannual” is an adjective used to describe events occurring twice a year. “Biannually” is the same, but in adverb form.

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.

Semiannual meaning

“Semiannual” is an adjective meaning something occurs twice a year. It is composed of two parts: “Semi-,” meaning half, and “annual,” meaning relating to one year. There is no difference between semiannual and biannual. These two terms are synonymous.

Semiannual or semi annual?

Semi-annual and semiannual are exactly the same and can be written either without or without the hyphen.

Semi is a prefix, and American English tends to use prefixes before the base word without a space or hyphen. On the other hand, British English favors joining the prefix to another word using a hyphen. A space should not separate the words. The same applies to biannual and bi-annual.

Biennial meaning

Biennial is an adjective meaning “takes place every two years.” It means that a recurring event happens one year, then misses a year, and takes place again the following year, and so on. The suffix “-ennial” means “years” and cannot be used alone, hence why it is always paired with a prefix denoting the number of years, in this case, “bi.” This term is also commonly used in gardening and botany to talk about plants. In a botanical context, “biennial” can be both an adjective to describe that a plant has a two-year lifecycle and a noun to refer to plants with a lifecycle of two years.

Learn English online and practice with an English tutor on LiveXP to figure out the difference and how to use these words.

Biannual, Semiannual, and Biennial Examples

The meeting is held every six months. It’s a biannual meeting.
We’ll discuss the results at your next semiannual appointment.
The biennial art festival takes place every two years.
He doesn’t attend the rally every month. He goes biannually.
The semiannual wedding show takes place in March and September.
The next biennial conference will take place next year.Sugar beets are biennial plants.

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