No, "biannual" is not hyphenated. It is a single word that means occurring twice a year. However, it is important to distinguish it from "biennial," which means occurring every two years. Always use "biannual" without a hyphen when referring to events that happen semiannually.
Biannual used in a sentence would be, "payments are going to be biannual". Biannual means that something is going to occur every two years.
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You will be in charge of the company's biannual recognition reception this upcoming June.
The Biannual Student Magazine
A biannual event is something that occurs twice a year.
The answer to this question is simple the affix of biannual is annual the suffix or prefix is bi
The answer to this question is simple the affix of biannual is annual the suffix or prefix is bi
Biannual can be used in a sentence as an adjective to denote an event that occurs twice a year, or every two years. So, "It's a biannual event" is a rather ambiguous statement.
Don't hyphenate; ongoing is one word.
You do not hyphenate the number.
I think it's more accepted to hyphenate it.
You hyphenate it only at the hyphen.