bi·an·nu·al | \(ˌ)bī-ˈan-yə(-wə)l \

Definition of biannual 

1 : occurring twice a year

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Other Words from biannual

biannually adverb

What do bimonthly and biweekly mean?: Usage Guide

Many people are puzzled about bimonthly and biweekly, which are often ambiguous because they are formed from two different senses of bi-: "occurring every two" and "occurring two times." This ambiguity has been in existence for nearly a century and a half and cannot be eliminated by the dictionary. The chief difficulty is that many users of these words assume that others know exactly what they mean, and they do not bother to make their context clear. So if you need bimonthly or biweekly, you should leave some clues in your context to the sense of bi- you mean. And if you need the meaning "twice a," you can substitute semi- for bi-. Biannual and biennial are usually differentiated.

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.

Examples of biannual in a Sentence

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 … 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 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 The group holds biannual meetings in December and July. The art show is a biannual event that won't happen again for two more years.
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Recent Examples on the Web

The fusion of her interests led her to create Chicago Theatre Now, a new biannual magazine that will discuss and explore issues of accountability, inclusion, diversity, and equity within the Chicago theater scene. Katie Powers, Chicago Reader, "Arts / Media / Theater Profiles abuse scandal inspires new magazine examining Chicago theater," 12 July 2018 The Sunshine State is on the verge of becoming sunnier — or at least brighter — every evening under a proposal to stop the biannual changing of the clocks and switch Florida to daylight saving time year-round. Linda Robertson, miamiherald, "Florida wants to tinker with time. Will it be the end of the clock as we know it? | Miami Herald," 8 Mar. 2018 Other actions Council approved a motion authorizing the city manager to enter into a biannual agreement with the city's current codification firm, Walter H. Drane Company. Brian Lisik/special To,, "Brunswick residents weigh in on city's master plan," 10 Apr. 2018 The city has also capitalized on temporary exhibits in recent years, including pop-up art demonstrations like the Art of Ice Cream Experience, as well as the city's biannual Canal Convergence. Lorraine Longhi, azcentral, "How Instagram is inspiring Scottsdale art for a new generation," 10 July 2018 The European Commission has launched a public poll on whether its biannual daylight saving rules should be scrapped for good. Shoshana Wodinsky, The Verge, "The EU is polling citizens if daylight saving is really necessary," 5 July 2018 Other bills aimed at the Illinois Department of Veterans’ Affairs would create a new protocol for reporting disease outbreaks and require biannual health reports to be sent to state lawmakers. Bill Lukitsch,, "More than 600 bills will land on Rauner’s desk as he seeks re-election," 10 June 2018 So a semiannual sale happens once every half a year – just like a biannual one. Melissa Mohr, The Christian Science Monitor, "Exactly how often is that?," 19 Apr. 2018 Chu says the biannual time switches are bad for people’s health and that there’s widespread support for more daylight in evening hours. Melody Gutierrez,, "Gas taxes, cage-free chickens and a chopped-up California top fall ballot," 3 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'biannual.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of biannual

1877, in the meaning defined at sense 1

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Statistics for biannual

Last Updated

14 Oct 2018

Look-up Popularity

Time Traveler for biannual

The first known use of biannual was in 1877

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More Definitions for biannual



English Language Learners Definition of biannual

: happening twice a year

: happening every two years

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Comments on biannual

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a state of commotion or excitement

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