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adjective bi·an·nu·al \(ˌ)bī-ˈan-yə(-wə)l\

Simple Definition of biannual

  • : happening twice a year

  • : happening every two years

Source: Merriam-Webster's Learner's Dictionary

Full Definition of biannual

  1. 1 :  occurring twice a year

  2. 2 :  biennial 1

biannually adverb

Usage Discussion of biannual

See Usage Discussion at bi-

Examples of biannual in a sentence

  1. Politicians still tremble when Barry begins his biannual comeback flirtations. … But if they'd spent less time looking over their shoulders and more time looking over election returns, they'd have seen that Barry was likely heading for a poleaxing when he called it quits. —Michael Schaffer, New Republic, 22 Apr. 2002

  2. … have recommended routine annual or biannual mammographic screening for asymptomatic women without a personal or family history of breast cancer, starting at the age of 40. —Nels Marcus Thygeson, Journal of the American Medical Association, 8 July 1986

  3. One of the more fascinating commonplace facts about the whitetail is its biannual change of color. Summer, when deer come “into the red,” as the saying goes, scant reddish-brown hairs replace the winter coat. Fall, deer come back “into the blue,” though less than blue, with a thick pelage of hollow, grayish-tan hairs … —John G. Mitchell, Smithsonian, November 1982

  4. The group holds biannual meetings in December and July.

  5. The art show is a biannual event that won't happen again for two more years.

Did You Know?

When we describe something as biannual, we can mean either that it occurs twice a year or that it occurs once every two years. So how does someone know which particular meaning we have in mind? Well, unless we provide them with a contextual clue, they don't. Some people prefer to use semiannual to refer to something that occurs twice a year, reserving biannual for things that occur once every two years. This practice is hardly universal among English speakers, however, and biannual remains a potentially ambiguous word. Fortunately, English also provides us with biennial, a word that specifically refers to something that occurs every two years or that lasts or continues for two years.


First Known Use of biannual


Other Number-Related Terms

Rhymes with biannual

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to expose to danger or risk

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